WO2017113030A1 - Method for producing orthopaedic and dental acrylic materials having antimicrobial properties, using copper nanoparticle technology - Google Patents

Method for producing orthopaedic and dental acrylic materials having antimicrobial properties, using copper nanoparticle technology Download PDF

Info

Publication number
WO2017113030A1
WO2017113030A1 PCT/CL2016/050079 CL2016050079W WO2017113030A1 WO 2017113030 A1 WO2017113030 A1 WO 2017113030A1 CL 2016050079 W CL2016050079 W CL 2016050079W WO 2017113030 A1 WO2017113030 A1 WO 2017113030A1
Authority
WO
WIPO (PCT)
Prior art keywords
dental
copper
acrylic
antimicrobial
cunps
Prior art date
Application number
PCT/CL2016/050079
Other languages
Spanish (es)
French (fr)
Inventor
Cristian Mauricio COVARRUBIAS GALLARDO
Sebastián Adolfo CORREA HERNÁNDEZ
Loreto Francisca MATAMALA LÓPEZ
Juan Pablo GONZÁLEZ ROJAS
Original Assignee
Universidad De Chile
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Family has litigation
First worldwide family litigation filed litigation Critical https://patents.darts-ip.com/?family=56610121&utm_source=google_patent&utm_medium=platform_link&utm_campaign=public_patent_search&patent=WO2017113030(A1) "Global patent litigation dataset” by Darts-ip is licensed under a Creative Commons Attribution 4.0 International License.
Application filed by Universidad De Chile filed Critical Universidad De Chile
Priority to EP16880234.6A priority Critical patent/EP3461335A4/en
Priority to MX2018008122A priority patent/MX2018008122A/en
Priority to US16/067,053 priority patent/US11134687B2/en
Publication of WO2017113030A1 publication Critical patent/WO2017113030A1/en
Priority to US17/404,858 priority patent/US20210400984A1/en

Links

Classifications

    • A—HUMAN NECESSITIES
    • A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
    • A01N—PRESERVATION OF BODIES OF HUMANS OR ANIMALS OR PLANTS OR PARTS THEREOF; BIOCIDES, e.g. AS DISINFECTANTS, AS PESTICIDES OR AS HERBICIDES; PEST REPELLANTS OR ATTRACTANTS; PLANT GROWTH REGULATORS
    • A01N59/00—Biocides, pest repellants or attractants, or plant growth regulators containing elements or inorganic compounds
    • A01N59/16—Heavy metals; Compounds thereof
    • A01N59/20—Copper
    • A—HUMAN NECESSITIES
    • A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
    • A01N—PRESERVATION OF BODIES OF HUMANS OR ANIMALS OR PLANTS OR PARTS THEREOF; BIOCIDES, e.g. AS DISINFECTANTS, AS PESTICIDES OR AS HERBICIDES; PEST REPELLANTS OR ATTRACTANTS; PLANT GROWTH REGULATORS
    • A01N55/00—Biocides, pest repellants or attractants, or plant growth regulators, containing organic compounds containing elements other than carbon, hydrogen, halogen, oxygen, nitrogen and sulfur
    • A01N55/02—Biocides, pest repellants or attractants, or plant growth regulators, containing organic compounds containing elements other than carbon, hydrogen, halogen, oxygen, nitrogen and sulfur containing metal atoms
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K33/00—Medicinal preparations containing inorganic active ingredients
    • A61K33/24—Heavy metals; Compounds thereof
    • A61K33/34—Copper; Compounds thereof
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K47/00—Medicinal preparations characterised by the non-active ingredients used, e.g. carriers or inert additives; Targeting or modifying agents chemically bound to the active ingredient
    • A61K47/30—Macromolecular organic or inorganic compounds, e.g. inorganic polyphosphates
    • A61K47/32—Macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds, e.g. carbomers, poly(meth)acrylates, or polyvinyl pyrrolidone
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K6/00—Preparations for dentistry
    • A61K6/70—Preparations for dentistry comprising inorganic additives
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K6/00—Preparations for dentistry
    • A61K6/80—Preparations for artificial teeth, for filling teeth or for capping teeth
    • A61K6/884—Preparations for artificial teeth, for filling teeth or for capping teeth comprising natural or synthetic resins
    • A61K6/887—Compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F1/00—Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
    • B22F1/10—Metallic powder containing lubricating or binding agents; Metallic powder containing organic material
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F9/00—Making metallic powder or suspensions thereof
    • B22F9/16—Making metallic powder or suspensions thereof using chemical processes
    • B22F9/18—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds
    • B22F9/24—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds starting from liquid metal compounds, e.g. solutions
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F1/00—Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
    • B22F1/05—Metallic powder characterised by the size or surface area of the particles
    • B22F1/054—Nanosized particles
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F2999/00—Aspects linked to processes or compositions used in powder metallurgy
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C1/00—Making non-ferrous alloys
    • C22C1/04—Making non-ferrous alloys by powder metallurgy
    • C22C1/0425—Copper-based alloys

Definitions

  • the objective of the present invention is part of a process for the production of a new acrylic biomaterial for the manufacture of dental or medical products with antlmicrobial properties, to be used in the control of the growth of microorganisms in the oral cavity or in orthopedic treatments, such as removable and fixed dental prostheses, restorative dental resin, restorative resin adhesive, orthodontic bracket adhesive, pit and fissure sealant or orthopedic bone cements based on copper nanoparticle technology and with anti-microbial properties against dental pathogens, especially Candida albicans, pathogen responsible for subprottic stomatitis or Streptococcus mutans, bacteria responsible for caries formation, as well as for Staphylococcus aureus that generates perlprothetic infections.
  • dental pathogens especially Candida albicans, pathogen responsible for subprottic stomatitis or Streptococcus mutans, bacteria responsible for caries formation, as well as for Staphylococcus aureus that generates perlprothetic infections.
  • dental prostheses continues to be the most widely used dental rehabilitation solution in the population, particularly in medium-low socioeconomic strata.
  • the cleaning of the prostheses is essential to maintain good oral hygiene and to prevent Subprottic Stomatitis, Chronic inflammation that can be generated in the oral mucosa in contact with the prosthesis, and that despite not having a defined etiology, one of its causes is the fungal infection of the genus Candida.
  • the ideal hygiene of the prosthesis is often not performed properly, in addition to the optical and pslcomotor limitations, characteristic conditions of the elderly patients.
  • the current treatment for this type of infection is the administration of oral and topical antimlcotic agents.
  • a nanocomposite is a material that combines materials of different nature, such as a polymer and a metal, where one of them has nanometric dimensions. Copper is a known antimicrobial, with antibacterial and antifungal properties; which are currently enhanced with the use of metal particles with nanometric dimensions.
  • Removable prostheses are the most commonly used alternative in rehabilitation of partially or totally toothless patients, especially in low-income groups and it is the main form of dental rehabilitation in primary care services, mainly due to its low cost.
  • the prostheses being an external element, produce on their surface the formation of a biofilm, which cannot be eliminated naturally.
  • This biofilm can cause a chronic inflammatory process of the mucosa adjacent to the prosthesis, which is known as Subprottic Stomatitis.
  • This pathology is characterized by inflammation and erythema of the mucosa covered by the prosthesis. It is asymptomatic, and only in some cases has a burning sensation, it is usually investigated by clinical examination. Although its etiology is not clearly defined, it is mainly associated with infection of the mucosa of Candida albicans and poor oral hygiene of patients (Gendreau, L. and ZG Loewy, Epidemiology and Etiology of Denture Stomatitis.
  • Candida albicans is a yeast that normally occurs in the oral cavity, gastrointestinal tract and vagina, living commensally. Its pathogenicity is regulated by its virulence factors and the result of its interaction with the host's immune response. (Schaller M, Borelli C, Korting HC, Hube B. Hydrolytic enzymes as virulence factors of Candida albicans. Mycoses. 2005; 48 (6): 365-77).
  • virulence factors are transcription factors for cell membrane proteins, adhesins, proteolytic enzymes, and lipolytic (Calderone RA, Fonzi WA. Virulence factors of Candida albicans. Trends in Microbiology.
  • Candida albicans is presented in the form of biofilm on the acrylic surface of dental prostheses, forming a closed matrix of yeast and hyphae microcolonies, containing a large number of bacteria, such as Streptococcus sps., Extracellular polymers, and even a different phenotype. which is presented in planktonic state.
  • Candida albicans has a high prevalence in the oral cavity, and it is common to find it in periodontal sacs, which may indicate a possible role in the genesis or exacerbation of the clinical conditions of Periodontal disease (Urz ⁇ a B., Hermosilla G ., Gamonal J., Morales-Bozo I., Canals M., Barahona S., et al. Yeast diversity in the oral microbiota of subjects with periodontitis: Candida albicans and Candida dubliniensis colonize the periodontal pockets.
  • Metals have known antimicrobial properties for centuries; and currently, its use in multiple applications is investigated with the help of nanotechnology, such as its application in surface disinfection and topical application in gels and pastes. Copper has It has been widely used in medicine since the 19th century, it was indicated in the treatment of skin infections, lupus, and was even an antimicrobial agent used until the appearance of antibiotics in 1932 (Grass, G., C. Rensing, and M Solioz, Metallic Copper as an Antimicrobial Surface Applied and Environmental Microbiology, 201 1.77 (5): p. 1541-1547).
  • nanotechnology The manipulation of the structure and application of materials with nanometric dimensions is what is known as nanotechnology, which is based on the control of the properties of materials on a nanometric scale (1-100 nm) for the purpose of exploiting, different characteristics of nanodimensional materials (Ravishankar Rai V. and Jamuna Bai A., Nanoparticles and their potential application as antimicrobials. Science against microbial pathogens: communicating current research and technological advances 201 1. 1 (1): p. 10). It is expected that with the development of nanotechnology important advances in the biological and biomedical sciences will be achieved, by delivering the tools that manage to understand the structures of materials and tissues, as well as design technologies to be able to explore, treat and possibly reconstruct them (Ahmed, W ., A. Elhissi, and K.
  • Nanoparticles due to their size, acquire new properties in relation to those observed in micrometric structures. These properties are determined by the effect generated by the atoms located in the surface layer of the structure and by presenting a greater surface area in relation to the volume of the nanoparticles, compared to that which occurs in micro or micro structures. macrometric (Ren, G., et al., Characterization of copper oxide nanoparticles for antimicrobial applications. International Journal of Antimicrobial Agents, 2009. 33 (6): p. 587-590).
  • AgNP Silver
  • Staphylococcus aureus Staphylococcus aureus
  • Klebsiella pneunomiae Ravishankar et al.
  • CuNP copper nanoparticles
  • CuNPs The antimicrobial properties of CuNPs have been evaluated so far against the bacteria Escherichia coli, Staphylococcus aureus, Klebsiella pneunomiae, Lysteria monocytogenes and Pseudomonas aeruginosa; as well as in front of the yeast Saccharomyces cerevisiae.
  • oral bacteria no evidence has been found in the prior art.
  • CuNPs have been used for the preparation of different polymeric nanocomposites with antimicrobial properties.
  • polymers such as CuNP-loaded polyvinyl ketone were studied, where the ability to release metal slowly and in a controlled manner was observed, as well as to inhibit the growth of bacteria and fungi such as Saccharomyces cervisiae; and the antimicrobial activity correlates directly with the concentration of nanoparticles (Cioffi et al.).
  • Other polymers studied are plant and bacterial cellulose matrices loaded with nanostructures, such as nanofilaments and CuNP, showing bactericidal action against Staphylococcus aureus and Klebsiella pneunomiae.
  • the oral cavity is a type of habitat where a group of microorganisms (microbial community) live.
  • microbial community a group of microorganisms
  • the manifestation of dental caries is mediated by complex mechanisms that are initiated by factors, including genetic, behavioral, environmental and microbial.
  • pathogens In the case of microbial factors, the presence of pathogens is essential for the onset and progression of caries lesions, without bacteria there is no injury.
  • pathogens is essential for the onset and progression of caries lesions, without bacteria there is no injury.
  • it is a polymicrobial infectious disease, where each individual bacterial species can collectively contribute to the total cariogenicity of the dental plaque bio-community (dental biofilm) associated with caries.
  • the intrinsic sources of nutrients for microorganisms of the oral cavity are the materials that are around the teeth, exudates, degraded epithelial cells and components of saliva, certain salivary proteins provide amino acids that influence the growth of Streptococcus mutans and Streptococcus sanguis; The saliva of caries subjects has a better influence on the growth of Streptococcus mutans.
  • the food we eat remains in the oral cavity, serving as an extrinsic source of nutrients for the oral microflora.
  • Dental caries is an infectious disease of multifactorial etiology, where microorganisms organized in a biofilm, called dental plaque, are a determining factor in the development of caries lesions, and this represents the late sign of the disease.
  • microbial species predominate, as a result of a succession of microorganisms.
  • the predominance of microorganisms other than those associated with the disease such as Streptococcus sanguinis, has been observed.
  • the streptococci belonging to the mutans group have been the predominant during the onset and progression of the lesion, especially Streptococcus mutans, while Lactobacillus and Bifidobacterium predominate in the advanced stages of the lesion.
  • Candida albicans which is a species of yeast that causes subprottic stomatitis that is caused by the use of a dental prosthesis; and generally said microorganism develops due to poor adjustment of said prosthesis or poor cleaning thereof.
  • Subprothetic stomatitis related to C. albicans is a non-specific inflammatory reaction to the antigens, toxins and microbial enzymes that are produced by the colonizing microorganisms, which is an infection of the oral mucosa, is a common and periodic disease that affects up to 67% of prosthesis users dental. It is known that factors, such as poor oral hygiene, high carbohydrate intake, reduced salivary flow, continuous use of the prosthesis, aging, malnutrition, immune suppression, radiation therapy, diabetes mellitus and possibly antibiotic treatment, increase susceptibility to C albicans
  • Biomaterials can be of artificial or biological origin.
  • Metal implants together with their alloys, are the most commonly used for orthopedic implants (nails, wires, plates) and dental implants (screws), since they must have a high resistance to mechanical wear and be able to withstand the appropriate load for their function.
  • the metals used to manufacture these implants are: stainless steel, cobalt alloys with chromium, molybdenum and nickel, pure titanium (Ti) and their alloys with aluminum and vanadium.
  • bone fragments, skin grafts, extracellular matrix to stem cells human or animal
  • extracellular matrix to stem cells human or animal
  • NPs inorganic nanoparticles
  • the microbicidal capacity of NPs is linked to the nature of the material and to certain intrinsic characteristics of them, such as their nanometric dimensions (which allows them to be more easily internalized in microorganisms) and the high area / volume ratio that allows greater contact. and interaction with these microorganisms.
  • metallic NPs that have been shown to have microbicidal properties, the most important are those of silver, zinc oxide, copper or iron oxides.
  • NPs have mechanisms of microbicidal action that are totally different from traditional antibiotics, thus providing a promising alternative.
  • the bactericidal action mechanisms of metallic NPs have not been fully elucidated, although several types of mechanisms have been postulated. Among which, disturbances in the functions of the cell membrane (which alter permeability and cellular respiration), the entry of nanoparticles into the cell, which causes an alteration in the functions of proteins and DNA, or the production of oxidative species due to the presence of NPs inside the cell.
  • the preparation of said dental material is based on the incorporation of copper nanoparticles (CuNPs) into the material by in-situ formation from a copper precursor or by direct addition prior synthesis.
  • CuNPs copper nanoparticles
  • the advantage of this technology lies in the fact that the commercial process currently used for the production of the prostheses is not altered, since it is based on the same resin currently used without altering it.
  • These new prosthetic devices with copper nanoparticle technology would have antifungal properties that would prevent and / or treat subprothetic stomatitis as well as reduce the amount of cariogenic bacteria in users with dental prostheses.
  • the technology proposed for the preparation of the antimicrobial prosthesis material considers the synthesis and / or incorporation of the CuNPs during the process of preparation of the prostheses that are currently marketed, which would facilitate the penetration of our methodology to the market.
  • RU 2444349 describes a modified adhesive composition for denture fixation, which contains a percentage by weight of: polyvinylpyrrolidone-5, polyacrylic acid -15, glycerol-4, antiseptic cetrimide; Sodium alginate-5, balsamic fir-10, silver nanoparticles of 1 to 5 nm size, and the rest distilled water.
  • the simplicity, safety and efficacy of the modified adhesive composition developed for the fixation of the denture allows it to be used in common orthopedic practice, where the adhesive composition provides considerable reduction of an adaptation length of dentureless patients with prostheses. In total, it does not cause any toxic action on the area tissues and the support body of the prosthesis as a whole and shows optimal adhesive properties, remaining unresolved for a long time with the intake of warm food.
  • US 2013014671 describes an antlmicroblane dental material characterized by the addition of about 0.1 to 0.5% by weight of antibacterial metal particles to a zirconium oxide (Zr0 2 ) as a powder substrate of antlmicroblane dental material.
  • the metallic material possesses excellent antlbacterial properties that release ions, which include: silver, gold, platinum, palladium, iridium, titanium, copper, tin, antimony, bismuth and zinc, especially it is preferred to use silver, copper and titanium. After being completely mixed and screened from the antibacterial metal particles it diffuses naturally in the zirconium oxide substrate, so that an antlmicroblane dental material is available for implants of dentures or prostheses or any other oral reconstruction.
  • US 6267590 describes a dental apparatus, such as orthodontic type, to be placed in the mouth and having an inorganic antimlcrobial agent on a surface, wherein the agent is preferably a zeollta.
  • the dental apparatus may comprise metal or a polymer (polycarbonate) and the agent may be present in a coating that is applied to the surfaces of the apparatus to be contacted by liquids or solids in the mouth.
  • the apparatus can be of a polymeric resin or an elastomer that incorporates the agent.
  • a preferred antlmicroblane agent is ceramic particles (for example, zeollta particles) containing antimlcrobial metal ions, for example, silver ions, as the active agent.
  • US 3,476,854 discloses a formulation of an acrylic material (alkyl methacrylates), slllcona resins, vlnyl copolymers, and polylamide to form coatings or conditioners for dentures, loaded with antifungal compounds of zinc carboxylates (undecylenate) ), which is dispersed in said resin, wherein said antlfungal agent is selected from heavy metal salts of monocarboxylic fatty acids, to medium chain length fatty acids, benzoic acid, benzoate of benzyl, salicylic acid, and benzyl salicylate, and said antifungal agent being present in said resin in an amount effective to retard fungal growth in said composition, and said amount being at least about 1% by weight of said composition.
  • EP 2536379 A2 describes an antibacterial dental prosthesis comprising a polymeric substrate with a functional polymer component and a releasable antifungal agent and which is attached to the functional polymer component such that the antifungal agent is slowly eluted from the polymer component. functional for a prolonged period of time.
  • EP 0081962 A2 describes a compressed solid composition for cleaning dentures that is very effervescent when added to water, which is composed of a mixture of perborate, dichloroisocyanurate and an alkali, which produces a pH cleaning solution. eleven .
  • EP 0400080 B1 describes a method of providing a dental prosthesis with a protective coating, which comprises applying to said prosthesis an aqueous dispersion of a coating of a non-toxic, antibacterial prosthesis polysaccharide, which reduces the adhesion of Streptococcus salivarius cells for acrylic resin prostheses by at least 25% compared to an uncoated control.
  • EP 1 003791 A4 describes a formulation of an adhesive and antimicrobial cleansing cream for dental prostheses, which comprises nystatin or a combination of 8-hydroxyquinoline (or its salt) and at least one copper (II) salt, wherein said formulation is to prevent prosthetic stomatitis by inhibiting Candida albicans.
  • US 4,332,791 describes an aqueous toothpaste composition containing at least one water soluble copper compound and at least one polishing agent, the majority of said polishing agent is silicon dioxide.
  • EP 0471396 describes an oral composition comprising a bicarbonate salt, a copper compound present in an amount effective to inhibit bacterial growth and a complexing agent present in an amount effective to stabilize the copper compound.
  • oral care forms comprising an anti-irritant amount of an icylate salt salt and an effective amount of a flavor enhancing agent, in addition to an anti amount -inflammatory of an irritant, for example ketorolac.
  • Such oral care formulations can be used in various devices to treat and / or prevent the irritation of mucous membranes such as ulcerations.
  • CuQ copper chalcogenide and / or copper halide
  • an antimicrobial barrier is created by incorporating CuQ nanoparticles of an adequate size and at a concentration necessary and sufficient to create a unique bioelectric environment.
  • the results of the unique bioelectric environment in biocidal efficiency is through a multi-factor mechanism that comprises a combination of the intrinsic quantum flow of copper ions (Cu 0 , Cu 1 + , Cu 2+ ) and the high electron sink from surface to volume facilitated by the nanoparticles.
  • said invention is directed to a bacteriostatic / bactericidal and anti-collagenolytic adhesive that is used to control the invasion and proliferation of microorganisms.
  • EP 1003791 A4 describes a formulation of an antimicrobial adhesive cream for dental prostheses, wherein the active principle of the adhesive consists of 8-hydroxyquinoline (0.0001-0, 5%) and a copper salt II (0.001 -0.3%) is the one that produces the most activity against C. albicans through in vitro assays.
  • the present invention is oriented to the development of a new material for the manufacture of a dental prosthesis device with antimicrobial properties, preferably to prevent subprothetic stomatitis caused by the Candida pathogen albicans, and the reduction of bacteria such as Streptococcus mutans, a pathogen responsible for the onset and progression of tooth decay.
  • the synthesis of the antimicrobial material for prostheses using copper nanoparticles as an antifungal agent is described in a preferred manner through the incorporation of copper nanoparticles into an acrylic thermosetting resin, which allows the generation of a prosthetic material with antimicrobial properties. especially against Candida albicans and particularly against Streptococcus mutans, in such a way to maintain the mechanical, color and cytocompatibility properties.
  • the present invention provides an antimicrobial CuNP / PMMA nanocomposite dental prosthesis material based on copper nanoparticles (CuNP) and polymethylmethacrylate (PMMA), comprising CuNP dispersed in said resin and formed in situ during the process of thermopolymerization from a copper salt as a precursor.
  • CuNP copper nanoparticles
  • PMMA polymethylmethacrylate
  • the present invention provides a nanocomposite material that includes copper nanoparticles (CuNP) and polymethylmethacrylate (PMMA) thermopolymerization CuNP / PMMA; wherein the applications of said nanocomposite material (acrylic polymers with CuNP) are made in: removable or fixed dental prostheses; dental restoration resins; resin adhesive (adhesive to bond the restoration resin to the tooth), pit and fissure sealant (acrylic sealant used to prevent the development of caries from minor fissures in the teeth, widely used in children), orthodontic adhesive (used to adhere the bracket on the surface of the tooth), ionomer glass (a versatile material in dentistry, which can be used as a restoration, temporary in adults or permanent in children, or as a cementing agent of other dental materials) and bone cement or surgical (self-curing acrylic used to fix orthopedic prostheses with bone or cranioplasty).
  • CuNP copper nanoparticles
  • PMMA polymethylmethacrylate
  • the present invention comprises an antimicrobial dental sealant comprising a dental sealant; and an antimicrobial dental resin that includes an antimicrobial amount of copper nanoparticles (CuNP) diffused therein.
  • the invention provides a method for preventing secondary dental caries including the application of a nanocomposite restorative dental resin based on copper nanoparticles (CuNP).
  • the invention provides a method for preventing or inhibiting tooth decay which comprises applying an antimicrobial dental sealant to pits and fissures of a tooth, wherein the antimicrobial sealant includes an antimicrobial dental resin that includes an antimicrobial amount of nanoparticles of copper (CuNP) diffused in it.
  • an antimicrobial dental sealant includes an antimicrobial dental resin that includes an antimicrobial amount of nanoparticles of copper (CuNP) diffused in it.
  • the present invention provides a method for inhibiting or limiting microbial growth in the area of enamel in contact with orthodontic brackets comprising the use of an orthodontic copper nanoparticle orthodontic adhesive (CuNP) diffused therein.
  • CuNP orthodontic copper nanoparticle orthodontic adhesive
  • the copper nanoparticles have a copper particle size of between 40 to 100 nm.
  • the removable prosthesis is currently the most widely used alternative in the rehabilitation of partially or totally toothless patients, especially in low-income groups, and is the main form of dental rehabilitation in the country's primary care services. Worldwide, this type of implements is widespread in the entire population in a high percentage.
  • the prostheses must have a maintenance linked mainly to their cleaning, a situation that is not always carried out properly, which is increased in the case of older adults.
  • This failure favors the formation of microbial plaque that in many cases generates inflammatory conditions of the oral mucosa, whose culture media are the remains of food deposited in the prosthesis.
  • the above results in the generation of a chronic inflammatory process of the mucosa adjacent to the prosthesis, known as subprothetic stomatitis.
  • the diagnosis of this pathology is fundamentally clinical and the symptomatology is variable, from asymptomatic to pictures with pain and / or burning of varied intensity in the compromised oral mucosa.
  • Subprothetic stomatitis is one of the alterations that is most frequently diagnosed within oral pathologies, and constitutes an oral health problem that requires more effective prevention and / or control alternatives.
  • This pathology can degenerate into a hyperplastic lesion if it is not treated in a timely manner. It usually occurs in the support mucosa, in patients with removable prostheses, which are commonly in poor condition.
  • Subprothetic stomatitis delimits and avoids the optimal use of removable prostheses, in addition that under this clinical condition the user must be treated according to the guide with specific topical antifungals, generating a relevant economic burden to the service responsible for the care.
  • stomatitis may be due to local factors such as the mismatch of the prosthesis, altered immune system or tobacco use;
  • This pathology is mainly generated by a microbial infection. It is estimated that a large percentage is the product of an exaggerated response of the organism against an infection of the mucosa by microorganisms that colonize the surface of the prosthesis, in most cases fungi of the genus Candida.
  • These pathogens are commensal members of the oral microbiota, and are present in about 40 percent of the population without causing problems in most of these.
  • its uncontrolled multiplication due to a period of immunosuppression or Due to the presence of local factors, it allows colonization of the patient's tissues.
  • Chronic Atrophic Candidiasis is that type of oral candidiasis that is directly associated with the use of removable prostheses, and is distinguished from other types of candidiasis because it occurs in areas that are covered by the devices, such as the hard palate, being seen as a Erythema and edema of the area.
  • Chronic atrophic candidiasis can manifest as well-defined hyperemic macules (Type I), as a diffuse erythema of part or all of the area covered by the prosthesis (Type II), or as a papillary (granular) hyperplasia that compromises the hard palate or the alveolar flange (Type III).
  • the most relevant microorganisms responsible for this infection are yeast species of the genus Candida, such as C. glabrata, C. tropicalis, C. kefyr, C. krusei and C.
  • Candida albicans is the most frequently isolated from lesions of the oral cavity [Williams DW, Kuriyama T, Silva S, Malic S, Lewis MA (2002), Candida biofilms and oral candidosis: treatment and prevention, Postgrad Med J; 78: 455-459]. It is considered that C. albicans first colonizes the back of the tongue and that, from there, it is able to invade other sites of the oral cavity such as the mucosa, dental pieces or dental materials that are secondary colonized [Webb BC, Thomas CJ, Willcox MD, Harty DW, Knox KW (201 1), Candida-associated denture stomatitis, Aetiology and management: a review.
  • C. albicans is the species that expresses a greater amount of virulence factors associated with pathogenicity, among which are: ability to adhere to host cells (adhesion to the mucosa), secretion of proteinases (tissue destruction), and morphology changes from yeast to pseudohyphae and hyphae.
  • the main mechanism that allows these microorganisms to be kept in the oral cavity is through the formation of biofilms on the surfaces. Biofilm protects yeasts from the mechanical removal action that produces saliva, and also functions as a protective barrier against the penetration of host immune response factors, as well as administered antimicrobials.
  • Candida initially adheres to the surfaces in the form of yeast, then proliferates through a growth of yeasts and the generation of multicellular filamentous extensions in the form of hyphae.
  • the existence of subprothetic stomatitis not only affects the quality of life of a large part of the population (60% of the 20% of the population that uses dentures), especially in the elderly, affecting their normal functions such as chewing, phonation and aesthetics, but it generates a great direct economic cost. This cost is related to the need for extra dental consultations, and to undergo controls and treatments that may consider the replacement of the device. From the country point of view, this pathology requires special planning in the public attention services, as well as the use of additional resources.
  • the treatment of a patient with oral candidiasis generally considers several aspects. As an essential part of the treatment, the patient is instructed in an appropriate hygiene technique that allows the complete removal of the biofilm, both from the surface of the mucosa and from the dental prosthesis. In addition to the mechanical removal procedures of biofilm, the use of mouthwashes that have activity against yeasts of the genus Candida such as chlorhexidine and triclosan is recommended. Patients are also emphasized the importance of quitting smoking, because tobacco generates a higher incidence of oral candidiasis In addition, it seeks to detect and correct any deficiency in the diet, such as an inappropriate intake of carbohydrate.
  • antlfungals are known that have proven effective for the treatment of candldiasls, such as pollens (Nistatlna, Amphotericin B), triazoles (Fluconazole, Itraconazole, Vorlconazole and Posaconazole), Equlnocandins (Caspofunglna, Micafunglna, Ancafunglna) , and Flucltosine.
  • pollens Nonistatlna, Amphotericin B
  • triazoles Fluonazole, Itraconazole, Vorlconazole and Posaconazole
  • Equlnocandins Caspofunglna, Micafunglna, Ancafunglna
  • Flucltosine Flucltosine.
  • these drugs can be administered topically or in a systemic way.
  • the use of antlfungals can also cause a series of adverse reactions, such as headaches, nausea, vomiting and gastrointestinal discomfort in general.
  • stremic drugs can be hepatotoxic, or generate neutropenla.
  • Systemic anif ⁇ nglcos in general also interact with other medications, so a complete history should be performed before prescribing them. It is for this reason that dentists try to avoid the use of sttemic antlfungals, and are only prescribed in clearly justified situations.
  • topical antlfungals are the first therapeutic line. These substances generally have a favorable response when used in direct contact with the lesion. However, topical administration is usually ineffective compared to the use of the disease, due to the need for frequent application of the drug on the affected surface, which is not always done by patients.
  • topical drugs are characterized by very unpleasant flavors, generate discomfort during use and keep for a short time in contact with the oral mucosa.
  • several adverse reactions can also occur due to the contact of the drug with the lesion, in this case the most important ones correspond to the irritation of the mucosa or the skin, alterations in the taste and burning of the area.
  • PMMA prosthetic acrylic
  • the new prostheses must maintain the structural properties of the original resin, without substantial alteration in their color or aesthetics.
  • an antimicrobial material for prostheses is developed, using elements and techniques currently offered by nanotechnology. Particularly, the use of metallic copper with nanometric particle size, unlike the use of copper salts more traditionally studied.
  • the new antifungal material corresponds to a nanocomposite, that is to say that composite material that combines materials of different nature where one of them has nanometric dimensions.
  • the preparation of this nanocomposite using the current prosthetic acrylic as a polymeric matrix and nanometric copper particles (CuNPs) as the antimicrobial component constitutes the central aspect of the invention.
  • the preparation of this nanocomposite material considers finding the most suitable conditions for the incorporation of the CuNPs in the matrix, but all that combined with the antimicrobial, aesthetic (color), mechanical and cytocompatibility properties of the resulting material.
  • the most traditional method for the preparation of polymeric nanocomposites consists in the physical mixing of the molten or dissolved polymer in some solvent with the nanoparticles (ex situ method).
  • the manufacture of a dental prosthesis is a polymerization process that occurs on a disposable material, which has the patient's dental record, given by the position of artificial teeth.
  • the ex situ method would require dissolving the already manufactured dental prostheses, which is why it is not feasible for this application.
  • the new prostheses must maintain the structural properties of the original resin, without substantial alteration in its color from the aesthetic - dental point of view.
  • the above raises the need to optimize the process of preparation of the nanocomposite prosthesis material based on the different properties (antlmicroblanes, mechanics, color), related to the type of copper particle, concentration, method of Incorporation and its distribution in the polymer matrix Among other variables.
  • the present invention focuses on the preparation of a nanocomposite material based on copper nanoparticles and thermoset polyethylene methacrylate; with anti-microbial properties against Candida albicans; optimizing its mechanical, cltocompatibility and aesthetic properties, which uses an in situ method of nanocomposite formation, incorporating the nanoparticles during the polymerization process.
  • the previously synthesized particles are incorporated by dispersing them in some of the reaction components (monomers, solvent), to then allow polymerization to occur.
  • the invention not only proposes the in situ preparation of the nanocomposite, but also CuNPS is synthesized during the polymerization process.
  • This process is based on the reducing properties that the metllmetacrllato monomer possesses, and that could be enhanced by the addition of small fractions of some organic solvent, such as ethanol.
  • the CuNPs can be formed by the reducing action of the monomer on copper ions incorporated from a metal salt.
  • This type of nanoparticle formation process in situ allows a more efficient incorporation and a more homogeneous dispersion of the particle in the nanocomposite matrix. These aspects are known factors that favor the blocking properties, mechanical and optical (color) of the composite obtained.
  • the preparation of the nanocomposite is considered, using CuNPs previously synthesized by other methods. In this case, commercially available CuNPs will be used, as well as CuNPs supported on particles of a ceramic material. This last approach also constitutes an important contribution from the scientific point of view.
  • Copper supported on ceramic matrices on average have a lower density and a lower impact on the coloration of polymeric composites.
  • a method has been developed that allows the synthesis of CuNPs on nanostructured ceramic materials such as zeolites or silica.
  • Zeolites are crystalline aluminosilicates that have a nanostructure consisting of pores, channels and cavities with sub-nanometric dimensions.
  • a copper-zeolite material can be obtained, where the metal nanoparticles are supported inside the cavities of the ceramic material.
  • the synthesis procedure of CuNPs supported on ceramic particles uses biocompatible reducing agents, which makes these materials particularly suitable for biomedical applications.
  • the dental prosthesis manufactured with the nanocomposite material has a marked antimicrobial effect against C. albicans and Streptococcus mutans due to the recognized antimicrobial properties of copper, particularly as an antifungal effective.
  • copper particles with nanometric size They should have a higher activity, which means that low metal contents can produce an important antimicrobial effect.
  • the antifungal properties of the nanocomposite are given by the fungicidal or antifouling effect of copper. These effects are produced by a controlled release of the copper particles from the polymer matrix, by exposing the nanocomposite with the aqueous medium.
  • Commonly polymeric matrices also suffer erosion in contact with the physiological environment, which would also facilitate the release of copper from the surface of the nanocomposite.
  • Topical antifungals are also particularly characterized by having unpleasant flavors, generating discomfort during use and keeping for a short time in contact with the oral mucosa. Due to the disadvantages of topical antifungals, as well as the limitations that patients have to follow the antifungal application protocols; New alternative solutions are required for this oral health problem. Strategies aimed at preventing the development of the disease are always more recommended for the health of the population.
  • the dental device made of a material specially formulated to have an antimicrobial effect against C. albicans, should significantly reduce the appearance of stomatitis caused by that pathogen. Therefore, the new prosthetic material is developed with elements currently delivered Nanotechnology This discipline based on the control of matter on a nanometric scale (10 ⁇ 9 m) to generate products with improved or new properties, is globally affecting various areas of industrial and social impact. In the dental field, the influence of nanomaterials can be found for example in the current dental restoration nanocomposites resins, which have greater durability and improved aesthetic properties.
  • nanometric copper have been found to be more effective as antimicrobial agents than microparticles, which opens up opportunities in nanotechnology in the field of antimicrobial materials. This justifies the use of these particles as agents to be incorporated in plastic matrices, as seen in other systems such as polymer / silver.
  • antimicrobial properties of nanometric copper are known in other fields of application, their use in dental products is not known, which constitutes a research and innovative component of this proposal.
  • the antimicrobial material consists of a nanocomposite, this is a composite material that combines materials of different nature (polymer and metal) and where some of them have nanometric dimensions.
  • the nanocomposite is constituted by a matrix of polymethylmethacrylate (PMMA), which will carry various copper nanoparticles (CuNPs). The selection of the matrix is based on its wide use in prosthetic applications, in order to facilitate its incorporation into the market.
  • PMMA polymethylmethacrylate
  • CuNPs copper nanoparticles
  • the present invention focuses on developing the most suitable technology for manufacturing the nanocomposite material, combining the preparation variables with their antimicrobial properties against C. albicans; as well as with its mechanical and aesthetic characteristics.
  • the nanocomposite formation process considers the in situ synthesis of the CuNPs during the polymerization of the PMMA, although alternatively the ex situ incorporation of the metal particles will also be considered, varying the percentage of charge in the matrix.
  • the objective is to find the best particle, its content in the polymer matrix and the most appropriate method for its incorporation, taking into account the antimicrobial, aesthetic and mechanics of the resulting nanocomposite material,
  • the preparation process of the nanocomposite is schematized in Figure 1.
  • a copper salt is used as a precursor to the CuNPs
  • the ex situ processes use pure powder CuNPs or a ceramic material such as zeolite or copper modified silica
  • the precursor CuNP is incorporated into the monomer, and then mixed with the polymer according to the traditional procedure of preparing acrylic prostheses and producing polymerization by self or thermosetting.
  • Figure 1 Scheme of the synthesis procedure of the CuNP / PMMA nanocomposite material. It is considered that by adding copper nanoparticles to the resin that is currently used in prostheses, a new antimicrobial material with aesthetic and mechanical properties similar to the resins currently used is generated. This is because copper is an effective antimicrobial agent, its nanoparticles being more effective than its microparticles. In addition, being the particles of nanometric size, these do not significantly affect the performance of the original matrix. All this justifies our approach based on nanotechnology.
  • the new nanocomposite material exerts an antimicrobial action mainly through the release of copper ions to the medium ( Figure 2).
  • the ions are released in a sustained manner from within the polymer matrix, which exert a fungicidal action on existing microorganisms that come into contact with the surface of the material or are located in the vicinity of the interface.
  • This mechanism reduces the viability and adhesion of the pathogen on the surface of the prosthetic material, as well as in the mucosa that is in contact with the dental device.
  • nanocomposites have a copper content of between approximately 30-150 ⁇ g / g.
  • the acrylic material of a prosthetic base has a mass of approximately 10 g, so a prosthesis made of the nanocomposite has maximum copper contents between 0.3-1.5 mg.
  • the composite material is synthesized through different in-situ synthesis strategies.
  • copper either as a precursor to the subsequent nanoparticle or as a particle already synthesized, is mixed with the monomer to collectively carry out the polymerization.
  • both the polymer and the nanoparticle are synthesized at the same stage by the addition of a copper precursor and the monomer;
  • the nanoparticle already synthesized is mixed with the monomer for subsequent polymerization.
  • two forms of copper nanoparticles were studied: metallic and copper supported on a ceramic matrix.
  • Fig. A shows an SEM microscopy image of the copper nanoparticles (CuNP) synthesized in situ in the acrylic monomer, where the average size of the CuNP is 40 nm and its nanometric nature was also confirmed by surface resonance plasmon. detected by the characteristic absorption band at 593 nm (see Fig. 1b).
  • Fig. 1b shows an SEM image of copper nanoparticles synthesized by the in situ method in acrylic monomer (a) and absorption spectrum indicating the surface resonance plasmon.
  • Figure 2a, 2b and 2c shows the presence of the copper nanoaprtircuas in the acrylic matrix of the nanocomposites that was confirmed by EDX elementary mapping, finding a relatively homogeneous distribution of the metal over the entire polymer matrix.
  • the FTIR analysis of the materials indicated that the spectra of the nanocomposites have all the bands corresponding to the PMMA spectrum, indicating that the chemical structure of the polymer is not altered with the incorporation of the metal nanoparticles.
  • Figure 2a shows a CuNP / PMMA nanocomposite SEM image
  • Figure 2b shows an EDX elementary mapping confirming the distribution of copper in the acrylic matrix
  • Figure 2c shows an FTIR-ATR analysis of PMMA acrylic and nanocomposite materials.
  • FIGURE 2a FIGURE 2b
  • Figures 3a and 3b show that nanocomposite materials with different contents of CuNP maintains the original mechanical properties of the PMMA control acrylic.
  • Figure 3a shows the mechanical property of flexural strength of PMMA acrylic and nanocomposts with different CuNP content
  • Figure 3b shows the mechanical property of the compression module of PMMA acrylic and nanocomposts with different CuNP content:
  • the results of the antimlcrobial activity of the nanocomposite materials against C. albicans was expressed as an ability to inhibit the growth of the microorganism on its surface with respect to the number of colonies grown in the PMMA control material without CuNP, which is defined by the following expression:
  • PMMA CFU Colony kiln units grown on the PMMA acrylic surface.
  • Figure 4 shows the capacity of inhibition of nanocomposite materials against C. albicans after 48 hours of incubation prepared with different CuNP contents, where it is observed that the acrylic nanocomposites of prepared prostheses have a copper content range between 0 , 01 5 to 0.068%, and which produce a range of percent inhibition between 65% to 92%, where the maximum capacity for growth inhibition of C. albicans with a CuNP content of 0.045% is obtained.
  • Figure 5 shows the ability to inhibit nanocomposite materials (CuNP / PMMA) against C. albicans at different incubation times, where it was found that the antimicrobial effect on the surface of the material continues over time.
  • Figure 7 shows the release of copper as a function of time from acrylic nanocomposites in artificial saliva (pH 6.5), where it is observed that the materials release very low concentrations of copper to the medium, with maximum values around 5.8x10 "3 ⁇ g / mL after 35 days of incubation in artificial saliva. However, these low Released copper levels are sufficient to produce the observed antimicrobial effect and at the same time maintain the biocompatibility of the new prosthetic material.
  • FIGURE 8 shows the viability of human fibroblast cells cultured at different incubation times with the current acrylic prosthesis material (PMMA) and the CuNP / PMMA nanocomposite measured by the MTS mitochondrial activity assay. It can be seen that the cell viability on the CuNP / PMMA nanocomposite is equivalent to that observed on the current PMMA acrylic prosthesis.
  • anti-mlbranch acrylics In the process of preparing anti-mlbranch acrylics, it can also be extended in the preparation of different acrylic materials for dental use, such as dental resins, adhesives for resins or orthodontic brackets, seals of occlusal pits and fissures as well as modified ionomer glasses with resin
  • acrylic monomers other than MMA such as Bls-GMA, TEGDMA, UDMA, HEMA or PENTA and can be polymerized by photo-curing, self-curing or by a dual system.
  • TABLE 1 shows the inhibition capabilities of the cariogenic S. mutans bacteria for the different nanocompost dental materials prepared by the ex situ process of CuNPs Incorporation.
  • the CuNP / PMMA nanocompost dental acrylic material also showed inhibitory capacity against the bacterium aggregatibacter actinomycetemcomitans (93% ⁇ 3), a pathogen representative of gingivitis and periodontitis.
  • the CuNP / PMMA nanocomposite preparation process can also be used for the manufacture of bone cement with antimicrobial properties.
  • Self-healing PMMA-based bone cement is used in orthopedics for the fixation of hip, knee, shoulder and other joint prostheses.
  • the bone cement based on CuNP / PMMA showed a capacity of inhibition of 94% ⁇ 3 against the Staphylococcus aureus bacteria, the main pathogen responsible for periprosthetic infections.
  • the present invention is aimed at developing a polymeric material with copper nanoparticles (CuNP), for which the composite material was synthesized by different ex situ and in situ situ synthesis strategies.
  • the compound can be prepared by the ex situ method, including by dividing the Cu N Ps / Zeo particles or copper nanoparticles (Cu N P) prepared ex situ by this or other methods.
  • copper either as a precursor to the subsequent nanoparticle or as a particle already synthesized; It is mixed with the monomer (PMMA) to collectively carry out the polymerization.
  • PMMA monomer
  • both the polymer and the nanoparticle were synthesized at the same stage by adding a precursor of an organic copper salt [Cu (CH 3 COO) 2 ] and the monomer;
  • the synthesized nanoparticle was mixed with the monomer for subsequent polymerization.
  • the preparation of CuNP / PMMA nanocomposts is detailed by an in situ synthesis of the nanocomposite material using self-curing or thermosetting polymerization.
  • aqueous solutions of copper acetate [Cu (CH 3 COO) 2 ] of different concentration (0.1-0.8 M) are used, preferably between 0.6-0.7 M, for which 100 ⁇ _ of The copper solution (Cu 2+ ) is added over 2 ml_ of absolute ethanol, to the resulting mixture is added under constant stirring 2 ml_ of the liquid dental monomer of methyl or methacrylate methyl methacrylate.
  • the resulting solution is maintained with constant stirring at temperatures between 50-70 ° C until the formation of the nanoparticles (CuNP), which is visualized by the appearance of the reddish coloration taken by the reaction mixture.
  • said solution of liquid monomer loaded with CuNPs is mixed with powdered dental acrylic in a 3: 2 ratio of acrylic mass: monomer volume (PMMA) to carry out the polymerization reaction under auto or thermoset conditions according to correspond.
  • the preparation of CuNP / PMMA composites using supported CuNPS is detailed.
  • the composite material was also prepared using Cu N Ps previously supported in part of a ceramic material.
  • the use of ceramic particles in particular could improve the coloring properties of the compound : as well as offering a different copper release kinetics from the material.
  • the density will be lower than in the case of metallic particles : therefore stability and decantation problems can be solved.
  • Zeolite particles al um nosil nanoporous crystalline icato
  • silica nanoparticles were used as support materials, for which, a natural zeolite of national origin (MO R) and nanoparticles of 1,00 ice ice were used commercial nm.
  • the Cu N Ps will be formed in situ in the material, for this Purpose certain mass of MOR was contacted with a 0.1 M copper acetate solution for 24 h at room temperature. After the ion exchange period was completed, the zeolite was separated and washed by repeated centrifugation / dispersion cycles. The material obtained was then dispersed in a starch / ascorbic acid reducing solution, and microwaved for certain seconds.
  • This system of formation of CuNPs in biopolymers was developed by our laboratory team, as a method under the concept of "Green Chemistry" for the synthesis of more benign metal nanoparticles, and compatible with biomedical applications.
  • the CuNPs / MOR particles were separated, washed and dried for later use in the process of preparing the CuNP / PMMA compound.
  • the compound was prepared by the ex situ method described above, incorporating the dehydrated CuNPs / MOR particles in the liquid methyl methacrylate monomer.
  • the preparation of CuNP / PMMA composites is detailed by means of an ex situ method of incorporating CuNP into self-curing or acrylic dental acrylic, where 5 nm CuNPs are used in powder and commercially available (Nanotec SpA, Chile).
  • the CuNPs were added to the methyl or methacrylate liquid monomer (4 mL) of auto or thermosetting, CuNP masses in the range of 0.79 - 6.28 mg, then dispersed in ultrasound for 10 minutes and then mixed with powdered dental acrylic in a 3: 2 ratio of acrylic mass / monomer volume (polymethylmethacrylate : with incorporated initiator) to give rise to the polymerization reaction), the polymerization is subsequently carried out under auto or thermoset conditions.
  • This example describes the in vitro evaluation of the antimicrobial properties of CuNPs / PMMA nanocomposites, for which a microbiological study using a strain ATCC 90029 of Candida albicans, from which broths of cultures with a concentration of 0.5 Mcfarland are prepared (1-5 x10 6 CFU / mi).
  • the samples of the CuNPs / PMMA nanocomposite material prepared with different CuNPs contents are incubated, as well as samples of the acrylic material without CuNPs as control (PMMA).
  • the incubation period is initially 48 hours at 37 S C under aerobic conditions.
  • the antimicrobial effect of the materials is evaluated by colony counting in the supernatant broth as well as on the surface of the materials.
  • dilutions of the culture broth are seeded in Sabouraud agar plates and incubated for 48 h at 37 ° C.
  • the microorganisms adhered to the surface of the material are removed by means of a harmless surfactant solution, to then be seeded and incubated in agar and perform the CFU count.
  • the antimicrobial effect of the materials was evaluated for a prolonged period of 10 days in contact with the microorganisms.
  • the cltocompatibility of nanocomposite materials was tested, for which it was evaluated by incubation in fibroblast cell cultures.
  • Cell viability was determined by the MTS (3- (4,5-dimethylthiazol-2-yl) 5- (3-carboxymethoxyphenyl) -2- (4-sulfophenyl) -2H-tetrazolium) mitochondrial activity spectrophotometric assay. , 5 and 10 days of incubation with the material.
  • the manufacturing of dental prostheses was performed using the nanocomposite material previously optimized based on its composition, antimicrobial, mechanical, aesthetic (color) and cytocompatibility properties.
  • two different manufacturing protocols normally used by dental laboratories were used.
  • the prostheses were manufactured in the facilities of the dental laboratories, according to established protocols regarding the temperature conditions, time and pressure of thermosetting; as well as the type of cuvettes, printing materials, muffles, and other elements used for the design of the prosthesis according to the characteristics of the patient.
  • Manufactured prostheses are evaluated according to dental criteria with respect to the mechanical properties of the acrylic base, stability of artificial teeth, aesthetic characteristics, among others.
  • the preparation of CuNP / acrylic nanocomposites is detailed by an ex situ method of incorporating CuNPs in dental restoration resin.
  • Powdered CuNPs are incorporated into a photocurate or dual system based on acrylic monomers, such as Bis-GMA, TEGDMA, UDMA or other, which may contain a micro or nanofill based on ceramic particles.
  • CuNPs concentrations are incorporated, preferably in the range 0.015 - 0.045% by weight.
  • the resulting mixture is treated by ultrasound by 1.0 minutes, then carry out the polymerization reaction by applying LED light for 40 seconds in the presence of camphorquinone as a photoinitiator.
  • the preparation of CuNP / acrylic nanocomposites is detailed, the preparation of CuNP / nanocomposites by means of an ex situ method of incorporating CuNPs into a dental restoration resin adhesive system.
  • Powdered CuNPs are incorporated into adhesive systems based on acrylic monomers such as UDMA or PENTA photocurate or dual. Concentrations of CuNPs are preferably incorporated in the range 0.015-0.045% by weight.
  • the resulting mixture is treated by ultrasound for 30 seconds, to then carry out the polymerization reaction by applying light L.E.D. for 10-30 seconds in the presence of camphorquinone as a photoinitiator or by dual polymerization.
  • the preparation of CuNP / acrylic nanocomposites using orthodontic adhesive acrylic by an ex situ method of incorporating CuNPs is detailed.
  • Powdered CuNPs are incorporated into adhesive systems for the cementation of orthodontic brackets based on acrylic monomers such as TEGDMA, Bis-GMA, UDMA, or HEMA photo or self-curing.
  • Concentrations of CuNPs are preferably incorporated in the range 0.01 5-0.045% by weight.
  • the resulting mixture is treated by ultrasound for 30 seconds, to then carry out the polymerization reaction by applying light L.E.D. for 10 seconds in the presence of camphorquinone as a photoinitiator or by self-polymerization.
  • the preparation of CuNP / acrylic nanocomposites is detailed by an ex situ method of incorporating CuNPs using ionomer glass modified with photopolymerizable acrylic resin used as cementing agent and restorative material in teeth temporary and as provisional in permanent teeth.
  • Powdered CuNPs are incorporated into the liquid ionomer glass of photo or self-curing at concentrations preferably in the range 0.01 5-0.045% by weight.
  • the resulting mixture is treated by ultrasound for 30 seconds, to then carry out the polymerization reaction by applying LED light for 10-30 seconds in the presence of camphorquinone as a photoinitiator or through self-curing polymerization.
  • the preparation of CuNP / acrylic nanocomposites is detailed by an ex situ method of incorporating CuNPs in pit and fissure sealants applied to occlusal surfaces of molar teeth that are especially susceptible to bacterial plaque buildup and subsequent development. of caries.
  • Powdered CuNPs are incorporated into the glass sealants based on acrylic monomers such as Bis-GMA or TEGDMA photo or self-curing at concentrations preferably in the range 0.015-0.045% by weight.
  • the resulting mixture is treated by ultrasound for 30 seconds, to then carry out the polymerization reaction by applying light L.E.D. for 10 -30 seconds in the presence of camphorquinone as a photoinitiator or through self-curing polymerization.
  • the preparation of CuNP / PMMA composites is detailed by an ex situ method of incorporating CuNP into bone cement acrylic used in the fixation of orthopedic prostheses, such as hip, knee, shoulder and other joint prostheses.
  • the CuNPs are incorporated in 4 mL of the liquid monomer / autocuration activator fraction in amounts of 0.79 - 6.28 mg, then dispersed in ultrasound for 10 minutes and then mixed with powdered bone acrylic in a proportion 3 : 2 acrylic mass (grams): monomer volume (mL). Subsequently polymerization is carried out under self-curing conditions.

Landscapes

  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • General Health & Medical Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Inorganic Chemistry (AREA)
  • Epidemiology (AREA)
  • Animal Behavior & Ethology (AREA)
  • Public Health (AREA)
  • Veterinary Medicine (AREA)
  • Oral & Maxillofacial Surgery (AREA)
  • Wood Science & Technology (AREA)
  • Agronomy & Crop Science (AREA)
  • Pest Control & Pesticides (AREA)
  • Plant Pathology (AREA)
  • Engineering & Computer Science (AREA)
  • Dentistry (AREA)
  • Zoology (AREA)
  • Environmental Sciences (AREA)
  • Medicinal Chemistry (AREA)
  • Pharmacology & Pharmacy (AREA)
  • Plastic & Reconstructive Surgery (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Dental Preparations (AREA)
  • Pharmaceuticals Containing Other Organic And Inorganic Compounds (AREA)
  • Toxicology (AREA)
  • Agricultural Chemicals And Associated Chemicals (AREA)
  • Cosmetics (AREA)
  • Polymers & Plastics (AREA)
  • Organic Chemistry (AREA)
  • Acyclic And Carbocyclic Compounds In Medicinal Compositions (AREA)
  • Adhesives Or Adhesive Processes (AREA)

Abstract

The invention relates to a novel biomaterial for the production of antimicrobial dental devices for use in controlling the growth of microorganisms in the oral cavity, such as removable dentures, using copper nanoparticle technology, having antimicrobial properties against dental pathogens, such as Candida albicans, the pathogen responsible for denture stomatitis, Streptococcus mutans, the pathogen responsible for the onset and progression of cavity formation, as well as Staphylococcus aureus which causes periprosthetic infections. According to the invention, the removable dental material can be used to produce a novel dental device for preventing and/or controlling oral infections caused by the aforementioned pathogens, such as, inter alia, denture stomatitis, secondary caries, and periodontal diseases.

Description

Proceso de preparación de materiales acrílicos dentales y ortopédicos con propiedades antimicrobianas mediante tecnología de nanopartículas de cobre.  Process of preparation of dental and orthopedic acrylic materials with antimicrobial properties through copper nanoparticle technology.
CAMPO DE LA INVENCIÓN. FIELD OF THE INVENTION
El objetivo de la presente Invención se enmarca en un proceso para la producción de un nuevo biomaterial acríllco para la fabricación de productos dentales o médicos con propiedades antlmicroblanas, para ser utilizado en el control del crecimiento de microorganismos en la cavidad oral o en tratamientos ortopédicos, tales como prótesis dentales removlbles y fijas, resina dental de restauración, adhesivo de resina de restauración, adhesivo de bracket ortodóntlco, sellante de fosas y fisuras o cementos óseos ortopédicos basado en tecnología de nanopartículas de cobre y con propiedades antlmicroblanas frente a patógenos dentales, especialmente Candida albicans, patógeno responsable de la estomatitis subprótesica o Streptococcus mutans, bacteria responsable de la formación de caries, así como para Staphylococcus aureus que genera Infecciones perlprotésicas. The objective of the present invention is part of a process for the production of a new acrylic biomaterial for the manufacture of dental or medical products with antlmicrobial properties, to be used in the control of the growth of microorganisms in the oral cavity or in orthopedic treatments, such as removable and fixed dental prostheses, restorative dental resin, restorative resin adhesive, orthodontic bracket adhesive, pit and fissure sealant or orthopedic bone cements based on copper nanoparticle technology and with anti-microbial properties against dental pathogens, especially Candida albicans, pathogen responsible for subprottic stomatitis or Streptococcus mutans, bacteria responsible for caries formation, as well as for Staphylococcus aureus that generates perlprothetic infections.
ANTECEDENTES DE LA INVENCIÓN. BACKGROUND OF THE INVENTION
El uso de prótesis dentales continúa siendo la solución de rehabilitación dental más utilizada dentro de la población, particularmente en estratos socioeconómicos medio bajos. La limpieza de las prótesis es esencial para mantener una buena higiene oral y para prevenir Estomatitis Subprótesica, Inflamación crónica que se puede generar en la mucosa oral en contacto con la prótesis, y que a pesar de no tener una etiología definida, una de sus causas es la Infección por hongos del género Candida. Siendo la gran mayoría de los portadores de prótesis adultos mayores, la higiene ideal de la prótesis muchas veces no es realizada adecuadamente, además de las limitaciones ópticas y pslcomotrices, condiciones características de los pacientes de la tercera edad. El actual tratamiento para este tipo de Infección es la administración de agentes antimlcóticos orales y tópicos. Sin embargo, este tipo de agentes puede conllevar efectos adversos para los pacientes, tales como malestar general y sabores particularmente desagradables. En la actualidad se busca desarrollar aproximaciones terapéuticas basadas en el diseño del material de prótesis, como la obtención de materiales nanocompósitos con actividad antimicrobiana. Un nanocompósito es un material que combina materiales de distinta naturaleza, como un polímero y un metal, en donde uno de ellos presenta dimensiones nanométricas. El cobre es un conocido antimicrobiano, con propiedades antibacterianas y antifúngicas; que son actualmente potenciadas con el uso de partículas del metal con dimensiones nanométricas. The use of dental prostheses continues to be the most widely used dental rehabilitation solution in the population, particularly in medium-low socioeconomic strata. The cleaning of the prostheses is essential to maintain good oral hygiene and to prevent Subprottic Stomatitis, Chronic inflammation that can be generated in the oral mucosa in contact with the prosthesis, and that despite not having a defined etiology, one of its causes is the fungal infection of the genus Candida. Being the great majority of the wearers of elderly prostheses, the ideal hygiene of the prosthesis is often not performed properly, in addition to the optical and pslcomotor limitations, characteristic conditions of the elderly patients. The current treatment for this type of infection is the administration of oral and topical antimlcotic agents. However, this type of agent can lead to adverse effects for patients, such as malaise and particularly unpleasant flavors. Currently, we seek to develop therapeutic approaches based on the design of the prosthetic material, such as obtaining nanocomposite materials with antimicrobial activity. A nanocomposite is a material that combines materials of different nature, such as a polymer and a metal, where one of them has nanometric dimensions. Copper is a known antimicrobial, with antibacterial and antifungal properties; which are currently enhanced with the use of metal particles with nanometric dimensions.
Las prótesis removibles son la alternativa más usada en rehabilitación de pacientes parcial o totalmente desdentados, especialmente en grupos de escasos recursos y es la principal forma de rehabilitación dental en los servicios de atención primaria, dado principalmente por su bajo costo. Removable prostheses are the most commonly used alternative in rehabilitation of partially or totally toothless patients, especially in low-income groups and it is the main form of dental rehabilitation in primary care services, mainly due to its low cost.
Las prótesis al ser un elemento externo, producen en su superficie la formación de un biofilm, el cual no puede ser eliminado de forma natural. Este biofilm puede provocar un proceso inflamatorio crónico de la mucosa adyacente a la prótesis, que se conoce como Estomatitis Subprótesica. Esta patología se caracteriza por la inflamación y eritema de la mucosa cubierta por la prótesis. Es asintomática, y sólo en algunos casos presenta sensación de ardor, por lo general es pesquisada mediante el examen clínico. A pesar de que su etiología no está claramente definida, se asocia principalmente a la infección de la mucosa de Candida albicans y a una pobre la pobre higiene oral de los pacientes (Gendreau, L. and Z.G. Loewy, Epidemiology and Etiology of Denture Stomatitis. Journal of Prosthodontics, 201 1 . 20(4): p. 251 -260). Estudios epidemiológicos hablan de una prevalencia que abarca un rango de 15 - 70% presentando mayor incidencia en adultos mayores y mujeres. En general, se considera que las dos terceras partes de los portadores de prótesis removibles, presentan estomatitis subprótesis en grado variable. The prostheses being an external element, produce on their surface the formation of a biofilm, which cannot be eliminated naturally. This biofilm can cause a chronic inflammatory process of the mucosa adjacent to the prosthesis, which is known as Subprottic Stomatitis. This pathology is characterized by inflammation and erythema of the mucosa covered by the prosthesis. It is asymptomatic, and only in some cases has a burning sensation, it is usually investigated by clinical examination. Although its etiology is not clearly defined, it is mainly associated with infection of the mucosa of Candida albicans and poor oral hygiene of patients (Gendreau, L. and ZG Loewy, Epidemiology and Etiology of Denture Stomatitis. Journal of Prosthodontics, 201 1.20 (4): p. 251-260). Epidemiological studies speak of a prevalence that covers a range of 15-70% presenting a higher incidence in older adults and women. In general, it is considered that two thirds of the wearers of removable prostheses have sub-prosthetic stomatitis in varying degrees.
Candida albicans es una levadura que se presenta normalmente en la cavidad oral, tracto gastrointestinal y vagina, viviendo de forma comensal. Su patogenicidad es regulada por sus factores de virulencia y el resultado de su interacción con la respuesta inmune del hospedero (Schaller M, Borelli C, Korting HC, Hube B. Hydrolytic enzymes as virulence factors of Candida albicans. Mycoses. 2005;48(6):365-77). Entre los factores de virulencia se encuentran factores de transcripción para proteínas de membrana celular, adhesinas, enzimas proteolíticas, y lipolíticas (Calderone RA, Fonzi WA. Virulence factors of Candida albicans. Trends in Microbiology. 2001 ;9(7):327-35), así también, posee la capacidad de adherirse a las células y penetrar el epitelio (Machado A., Komiyama E., Santos S., Jorge A., Brighenti F., Koga-lto C, In vitro adherence of Candida albicans isolated from patients with chronic periodontitis. J Appl Oral Sci. 2010; 384-387). Además, Candida albicans se presenta en forma de biofilm sobre la superficie del acrílico de prótesis dentales, formando una matriz cerrada de microcolonias de levaduras e hifas, conteniendo un gran número de bacterias, como Streptococcus sps., polímeros extracelulares, e incluso un fenotipo distinto al que se presenta en estado planctónico. Esta conformación la hace mucho más resistente a agentes antimicrobianos (Douglas LJ. Candida biofilms and their role in infection. Trends in Microbiology. 2003;1 1 (1 ):30- 6). Además, Candida albicans posee una alta prevalencia en la cavidad oral, y es común encontrarla en sacos periodontales, lo que nos pueden indicar un posible rol en la génesis o en la exacerbación de las condiciones clínicas de enfermedad Periodontal (Urzúa B., Hermosilla G., Gamonal J., Morales-Bozo I., Canals M., Barahona S., et al. Yeast diversity in the oral microbiota of subjects with periodontitis: Candida albicans and Candida dubliniensis colonize the periodontal pockets. Med Mycol. 2008; 46:783-93; y Sardi J., Duque C, Mariano F., Peixoto I., Hofling J., Goncalves B. Candida spp. in periodontal disease: a brief review. J Oral Science. 2010. Vol. 52, No. 2, 177-185). En los pacientes con periodontitis refractaria, el 83.3% de los sacos periodontales poseen Candida albicans, lo que nos indica una relación entre ésta y la infraestructura de la microbiota periodontal (Machado et al). Canabarro et al., (Canabarro A., Valle C, Farias MR., Santos FB, Lazera M., Wanke B. Association of subgingival colonizaron of Candida albicans and other yeast with severity of chrionic periodontitis. J Periodont Res 2013; 48: 428-432) han hipotetizado que la profunda perturbación epitelial estructural en el saco periodontal y la inmunosupresión causada por la severidad de la enfermedad periodontal, facilitaría la colonización de Candida albicans subgingival. Por lo tanto existen, claras evidencias de la coexistencia de Candida albicans, responsable de la estomatitis y de los patógenos periodontales. El tratamiento de primera opción para estomatitis subprótesica, es la aplicación de antifúngicos sistémicos y tópicos, como la Nistatina y el Fluconazol. Éstos antimicóticos pueden presentar efectos adversos como dolores de cabeza, náuseas, vómitos y malestar general; además de generar incomodidad y sabor desagradable para el paciente, lo que aumenta la descontinuación de este tipo de tratamiento. Se conoce que el tratamiento con antifúngicos tópicos resulta exitoso en erradicar la contaminación por Candida albicans y aliviar sus síntomas, pero si no se realiza una apropiada y mantenida higiene de las prótesis, la estomatitis subprótesis volverá a recurrir una vez terminado el tratamiento (Gendreau et al). Candida albicans is a yeast that normally occurs in the oral cavity, gastrointestinal tract and vagina, living commensally. Its pathogenicity is regulated by its virulence factors and the result of its interaction with the host's immune response. (Schaller M, Borelli C, Korting HC, Hube B. Hydrolytic enzymes as virulence factors of Candida albicans. Mycoses. 2005; 48 (6): 365-77). Among the virulence factors are transcription factors for cell membrane proteins, adhesins, proteolytic enzymes, and lipolytic (Calderone RA, Fonzi WA. Virulence factors of Candida albicans. Trends in Microbiology. 2001; 9 (7): 327-35 ), also, has the ability to adhere to the cells and penetrate the epithelium (Machado A., Komiyama E., Santos S., Jorge A., Brighenti F., Koga-lto C, In vitro adherence of Candida albicans isolated from patients with chronic periodontitis. J Appl Oral Sci. 2010; 384-387). In addition, Candida albicans is presented in the form of biofilm on the acrylic surface of dental prostheses, forming a closed matrix of yeast and hyphae microcolonies, containing a large number of bacteria, such as Streptococcus sps., Extracellular polymers, and even a different phenotype. which is presented in planktonic state. This conformation makes it much more resistant to antimicrobial agents (Douglas LJ. Candida biofilms and their role in infection. Trends in Microbiology. 2003; 1 1 (1): 30-6). In addition, Candida albicans has a high prevalence in the oral cavity, and it is common to find it in periodontal sacs, which may indicate a possible role in the genesis or exacerbation of the clinical conditions of Periodontal disease (Urzúa B., Hermosilla G ., Gamonal J., Morales-Bozo I., Canals M., Barahona S., et al. Yeast diversity in the oral microbiota of subjects with periodontitis: Candida albicans and Candida dubliniensis colonize the periodontal pockets. Med Mycol. 2008; 46 : 783-93; and Sardi J., Duke C, Mariano F., Peixoto I., Hofling J., Goncalves B. Candida spp. In periodontal disease: a brief review. J Oral Science. 2010. Vol. 52, No .2, 177-185). In patients with refractory periodontitis, 83.3% of the periodontal sacs have Candida albicans, which indicates a relationship between it and the periodontal microbiota infrastructure (Machado et al). Canabarro et al., (Canabarro A., Valle C, Farias MR., Santos FB, Lazera M., Wanke B. Association of subgingival colonized of Candida albicans and other yeast with severity of chrionic periodontitis. J Periodont Res 2013; 48: 428-432) have hypothesized that the deep structural epithelial disturbance in the periodontal sac and immunosuppression caused by the severity of periodontal disease would facilitate colonization of subgingival Candida albicans. Therefore, there is clear evidence of the coexistence of Candida albicans, responsible for stomatitis and periodontal pathogens. The first choice treatment for subprottic stomatitis is the application of systemic and topical antifungals, such as Nystatin and Fluconazole. These antifungals can present adverse effects such as headaches, nausea, vomiting and general malaise; In addition to generating discomfort and unpleasant taste for the patient, which increases the discontinuation of this type of treatment. It is known that treatment with topical antifungals is successful in eradicating Candida albicans contamination and relieving its symptoms, but if proper and maintained hygiene of the prostheses is not performed, the sub-prosthetic stomatitis will recur once the treatment is finished (Gendreau et to the).
Buscando nuevas alternativas terapéuticas, se ha observado que la modificación de las características de la superficie del material acrílico, es un método efectivo en reducir la adhesión de Candida albicans a la prótesis (Park, S.E., et al., Candida albicans Adherence to Surface-Modified Denture Resin Surfaces. Journal of Prosthodontics, 2008. 17(5): p. 365-369). Mediante modificaciones de las propiedades químico físicas de los materiales de uso médico, es posible otorgarles propiedades antimicrobianas, y así prevenir y controlar las infecciones. En esta línea, se han realizado estudios orientados a incorporar compuestos antifúngicos al acrílico de prótesis, como modificar la superficie del acrílico mediante una impregnación de la superficie del acrílico con histaminas y defensinas salivales (Pusateri CR, Monaco EA, Edgerton M. Sensitivity of Candida albicans biofilm cells grown on denture acrylic to antifungal proteins and chlorhexidine. Archives of Oral Biology. 2009;54(6):588-94). Redding et al., prepararon un recubrimiento polimérico cargado con clorhexidina, nistatina y anfotericina, siendo el recubrimiento de clorhexidina el que obtuvo mejores resultados ((Redding S, Bhatt B, Rawls HR, Siegel G, Scott K, Lopez-Ribot J. Inhibition of Candida albicans biofilm formation on denture material. Oral Surgery, Oral Medicine, Oral Pathology, Oral Radiology, and Endodontology. 2009;1 07(5):669-72). Looking for new therapeutic alternatives, it has been observed that the modification of the surface characteristics of the acrylic material is an effective method in reducing the adhesion of Candida albicans to the prosthesis (Park, SE, et al., Candida albicans Adherence to Surface- Modified Denture Resin Surfaces, Journal of Prosthodontics, 2008. 17 (5): p. 365-369). By modifications of the physical chemical properties of medical materials, it is possible to grant them antimicrobial properties, and thus prevent and control infections. Along these lines, studies have been carried out to incorporate antifungal compounds to prosthetic acrylic, such as modifying the surface of the acrylic by impregnating the surface of the acrylic with histamines and salivary defensins (Pusateri CR, Monaco EA, Edgerton M. Sensitivity of Candida albicans biofilm cells grown on denture acrylic to antifungal proteins and chlorhexidine Archives of Oral Biology. 2009; 54 (6): 588-94). Redding et al., Prepared a polymeric coating loaded with chlorhexidine, nystatin and amphotericin, being the chlorhexidine coating the one that obtained better results ((Redding S, Bhatt B, Rawls HR, Siegel G, Scott K, Lopez-Ribot J. Inhibition of Candida albicans biofilm formation on denture material Oral Surgery, Oral Medicine, Oral Pathology, Oral Radiology, and Endodontology. 2009; 1 07 (5): 669-72).
Los metales presentan propiedades antimicrobianas conocidas por siglos; y actualmente, se investiga su uso en múltiples aplicaciones con la ayuda de la nanotecnología, como su aplicación en desinfección de superficies y aplicación tópica en geles y pastas. El cobre, ha sido muy utilizado en medicina desde el siglo 19, era indicado en el tratamiento de infecciones de piel, lupus, e incluso fue un agente antimicrobiano utilizado hasta la aparición de los antibióticos el año 1932 (Grass, G., C. Rensing, and M. Solioz, Metallic Copper as an Antimicrobial Surface. Applied and Environmental Microbiology, 201 1 . 77(5): p. 1541 -1547). Además, el cobre se ha utilizado por décadas por sus propiedades antimicóticas (Cioffi , N., Torsi, L, Ditarantano, N., Tantalillo, G., Ghibelli, L, Sabbatini, L, Bleve-Zacheo, T., D'Alessio, M., Zambonin, PG., Traversa, E., Copper nanoparticle/polymer composites with antifungal and bacteriostatic properties. Chem. Mater, 2005, 17, 5255-5262; y Palza, H., Quijada, R., Delgado, K., Antimicrobial polymer composites with copper micro- and nanoparticles: Effect of particle size and polymer matrix. Journal of Bioactive and compatible polymers. 201 5, 1 -15). Sin embargo, en los últimos años ha resurgido el interés por el uso de las propiedades antimicrobianas de este metal, principalmente debido a la posibilidad de producir partículas de cobre con tamaño nanométrico. Metals have known antimicrobial properties for centuries; and currently, its use in multiple applications is investigated with the help of nanotechnology, such as its application in surface disinfection and topical application in gels and pastes. Copper has It has been widely used in medicine since the 19th century, it was indicated in the treatment of skin infections, lupus, and was even an antimicrobial agent used until the appearance of antibiotics in 1932 (Grass, G., C. Rensing, and M Solioz, Metallic Copper as an Antimicrobial Surface Applied and Environmental Microbiology, 201 1.77 (5): p. 1541-1547). In addition, copper has been used for decades for its antifungal properties (Cioffi, N., Torsi, L, Ditarantano, N., Tantalillo, G., Ghibelli, L, Sabbatini, L, Bleve-Zacheo, T., D ' Alessio, M., Zambonin, PG., Traversa, E., Copper nanoparticle / polymer composites with antifungal and bacteriostatic properties. Chem. Mater, 2005, 17, 5255-5262; and Palza, H., Quijada, R., Delgado , K., Antimicrobial polymer composites with copper micro- and nanoparticles: Effect of particle size and polymer matrix. Journal of Bioactive and compatible polymers. 201 5, 1-15). However, in recent years interest in the use of the antimicrobial properties of this metal has resurfaced, mainly due to the possibility of producing copper particles with nanometric size.
La manipulación de la estructura y aplicación de materiales con dimensiones nanométrica es lo que se conoce como nanotecnología, la cual se basa en el control de las propiedades de los materiales a una escala nanométrica (1 -100 nm) con el propósito de explotar, las características distintas que posee los materiales nanodimensionales (Ravishankar Rai V. and Jamuna Bai A., Nanoparticles and their potential application as antimicrobials. Science against microbial pathogens: communicating current research and technological advances 201 1 . 1 (1 ): p. 10). Se espera que con el desarrollo de la nanotecnología se logren avances importantes en las ciencias biológicas y biomédicas, al entregar las herramientas que logren comprender las estructuras de materiales y tejidos, así como diseñar tecnologías para poder explorarlas, tratarlas y posiblemente reconstruirlas (Ahmed, W., A. Elhissi, and K. Subramani, Chapter 1 - Introduction to Nanotechnology, in Nanobiomaterials in Clinical Dentistry, K.S.A.K. Hartsfield, Editor. 2013, William Andrew Publishing. p. 3-16). Las nanopartículas por su tamaño adquieren nuevas propiedades en relación a las observadas en estructuras de tamaño micrométrico. Estas propiedades están determinadas por el efecto que generan los átomos ubicados en la capa superficial de la estructura y por presentar una mayor área superficial en relación al volumen de las nanopartículas, en comparación a la que se da en las estructuras micro o macrométricas (Ren, G., et al., Characterisation of copper oxide nanoparticles for antimicrobial applications. International Journal of Antimicrobial Agents, 2009. 33(6): p. 587-590). Una de las nanopartículas metálicas más estudiadas es la de Plata (AgNP), las cuales han demostrado propiedades antibacterianas frente Escherichia coli, Staphylococcus aureus, y Klebsiella pneunomiae (Ravishankar et al.). The manipulation of the structure and application of materials with nanometric dimensions is what is known as nanotechnology, which is based on the control of the properties of materials on a nanometric scale (1-100 nm) for the purpose of exploiting, different characteristics of nanodimensional materials (Ravishankar Rai V. and Jamuna Bai A., Nanoparticles and their potential application as antimicrobials. Science against microbial pathogens: communicating current research and technological advances 201 1. 1 (1): p. 10). It is expected that with the development of nanotechnology important advances in the biological and biomedical sciences will be achieved, by delivering the tools that manage to understand the structures of materials and tissues, as well as design technologies to be able to explore, treat and possibly reconstruct them (Ahmed, W ., A. Elhissi, and K. Subramani, Chapter 1 - Introduction to Nanotechnology, in Nanobiomaterials in Clinical Dentistry, KSAK Hartsfield, Editor. 2013, William Andrew Publishing. P. 3-16). Nanoparticles, due to their size, acquire new properties in relation to those observed in micrometric structures. These properties are determined by the effect generated by the atoms located in the surface layer of the structure and by presenting a greater surface area in relation to the volume of the nanoparticles, compared to that which occurs in micro or micro structures. macrometric (Ren, G., et al., Characterization of copper oxide nanoparticles for antimicrobial applications. International Journal of Antimicrobial Agents, 2009. 33 (6): p. 587-590). One of the most studied metal nanoparticles is that of Silver (AgNP), which have demonstrated antibacterial properties against Escherichia coli, Staphylococcus aureus, and Klebsiella pneunomiae (Ravishankar et al.).
Con respecto a las nanopartículas de cobre (CuNP), se han observado mejores propiedades antimicrobianas, en comparación al tamaño micro (Theivasanthi, T., Studies of Copper Nanoparticles Effects on Micro-organisms. Annals of Biological Research, 201 1 . 2(3): p. 368- 373). También han sido efectivas al matar numerosas cepas de infecciones intrahospitalarias, aunque se observa la necesidad de la liberación controlada de iones al ambiente local, para lograr una actividad antimicrobiana óptima (Ren, G., et al.). Las propiedades antimicrobianas de CuNPs han sido evaluadas hasta ahora frente a las bacterias Escherichia coli, Staphylococcus aureus, Klebsiella pneunomiae, Lysteria monocytogenes y Pseudomonas aeruginosa; como también frente a la levadura Saccharomyces cerevisiae. Sin embargo, referente a bacterias orales no se ha encontrado evidencia en el arte previo. With respect to copper nanoparticles (CuNP), better antimicrobial properties have been observed, compared to micro size (Theivasanthi, T., Studies of Copper Nanoparticles Effects on Micro-organisms. Annals of Biological Research, 201 1. 2 (3 ): p. 368-373). They have also been effective in killing numerous strains of in-hospital infections, although the need for controlled release of ions to the local environment is observed, to achieve optimal antimicrobial activity (Ren, G., et al.). The antimicrobial properties of CuNPs have been evaluated so far against the bacteria Escherichia coli, Staphylococcus aureus, Klebsiella pneunomiae, Lysteria monocytogenes and Pseudomonas aeruginosa; as well as in front of the yeast Saccharomyces cerevisiae. However, regarding oral bacteria no evidence has been found in the prior art.
Estudios referentes al mecanismo bactericida del cobre como nanopartícula, indican que el efecto se atribuye a su pequeño tamaño y a su gran superficie de contacto, en relación a su volumen, lo que le permite interactuar fácilmente con las membranas microbianas (Chatterjee AK, Ruchira C, Tarakdas B. Mechanism of antibacterial activity of copper nanoparticles. Nanotechnology. 2014;25(13):135101 ). Un método de acción muy aceptado es la muerte celular por contacto, la cual se produciría por una serie de eventos sucesivos, desde el daño a la membrana celular, la entrada de cobre hacia la célula, la formación de especies reactivas del oxígeno por iones cobre que participan en la reacción redox y la posterior degradación del DNA, produciendo muerte celular (Grass et al.). En un estudio del año 2014, se reportaron nuevos antecedentes acerca del mecanismo de acción antibacteriano de las nanopartículas de cobre. En el estudio de CuNP sobre Escherichia coli, se observó un cambio de la morfología bacteriana hacia una formación filamentosa y posterior muerte celular. Este efecto se atribuye a la respuesta celular causada por una sobreproducción de especies reactivas del oxígeno, lo que resulta en una considerable peroxidación lípidica, oxidación de proteínas y degradación de DNA (Chatterjee et al.)- Sin embargo, los autores también concluyen que probablemente no existe un solo mecanismo de acción bactericida para las CuNP, pudiendo ser el agente activo tanto la nanopartícula misma o los iones metálicos que se liberan desde la partícula. Las últimas evidencias indican que el mayor efecto antimicrobiano sería producido por la liberación de iones desde las nanopartículas (Palza, H., Antimicrobial Polymers with Metal Nanoparticles. Int. J. Mol. Sci. 2015, 16, 2099-21 16). Studies concerning the bactericidal mechanism of copper as a nanoparticle, indicate that the effect is attributed to its small size and large contact area, in relation to its volume, which allows it to easily interact with microbial membranes (Chatterjee AK, Ruchira C, Tarakdas B. Mechanism of antibacterial activity of copper nanoparticles. Nanotechnology. 2014; 25 (13): 135101). A widely accepted method of action is cell death by contact, which would be caused by a series of successive events, from damage to the cell membrane, the entry of copper into the cell, the formation of reactive oxygen species by copper ions involved in the redox reaction and subsequent degradation of DNA, causing cell death (Grass et al.). In a 2014 study, new antecedents were reported about the mechanism of antibacterial action of copper nanoparticles. In the CuNP study on Escherichia coli, a change in bacterial morphology towards a filamentous formation and subsequent cell death was observed. This effect is attributed to the cellular response caused by an overproduction of reactive oxygen species, which which results in considerable lipid peroxidation, protein oxidation and DNA degradation (Chatterjee et al.) - However, the authors also conclude that there is probably no single mechanism of bactericidal action for CuNP, the active agent being both the same nanoparticle or metal ions that are released from the particle. The latest evidence indicates that the greatest antimicrobial effect would be produced by the release of ions from the nanoparticles (Palza, H., Antimicrobial Polymers with Metal Nanoparticles. Int. J. Mol. Sci. 2015, 16, 2099-21 16).
Por otra parte, no se han realizados estudios con nanopartículas de cobre sobre el efecto con Candida albicans, pero si se encuentran estudios con AgNP, en donde se han reportado los efectos de AgNP usadas tópicamente sobre biofilm de Candida albicans (Monteiro, D.R., et al., Silver colloidal nanoparticle stability: influence on Candida biofilms formed on denture acrylic. Medical Mycology, 2014. 52(6): p. 627-635); y Candida glabrata (Silva, S., et al., The effect of silver nanoparticles and nystatin on mixed biofilms of Candida glabrata and Candida albicans on acrylic. Medical Mycology, 2013. 51(2): p. 178- 184) formado sobre superficies de acrílico, exhibiendo efectos biocidas para ambas cepas. On the other hand, there have been no studies with copper nanoparticles on the effect with Candida albicans, but there are studies with AgNP, where the effects of AgNP used topically on biofilm of Candida albicans have been reported (Monteiro, DR, et al., Silver colloidal nanoparticle stability: influence on Candida biofilms formed on denture acrylic, Medical Mycology, 2014. 52 (6): p. 627-635); and Candida glabrata (Silva, S., et al., The effect of silver nanoparticles and nystatin on mixed biofilms of Candida glabrata and Candida albicans on acrylic. Medical Mycology, 2013. 51 (2): p. 178-184) formed on Acrylic surfaces, exhibiting biocidal effects for both strains.
Debido a la capacidad antimicrobiana de estas partículas se explorado la posibilidad de modificar el material acrílico de prótesis, incorporando nanopartículas metálicas a su matriz polimérica. Kamikawa et al. evaluó la adherencia de Candida albicans y Candida glabrata sobre acrílicos dentales modificados con un recubrimiento polímerico cargado con AgNP, observando una considerable reducción en el crecimiento de colonias de Candida albicans (Kamikawa, Y., et al., In Vitro Antifungal Activity against Oral Candida Species Using a Denture Base Coated with Silver Nanoparticles. Journal of Nanomaterials, 2014. 2014: p. 6). En otros enfoques, se ha ensayado la incorporación de AgNP en el interior de la resina de acrílico. Estos materiales tendrían la capacidad liberar en forma controlada el agente activo y así controlar la proliferación de los microorganismos en la superficie de la prótesis. La existencia de una prótesis dental con éstas características antimicrobianas, permitiría prevenir y tratar la estomatitis, a diferencia de la terapia antimicótica que sólo trata la enfermedad. Utilizando esta estrategia de modificación del material acrílico, (Nam K-Y, Lee C-H, Lee C-J. Antifungal and physical characteristics of modified denture base acrylic incorporated with silver nanoparticles. Gerodontology. 2012;29(2):e413-e9), incorporaron AgNP a acrílicos de prótesis dentales, mezclando suspensiones coloidales de plata con el acrílico, por medio de utilizar contenidos de plata entre 20- 30% en peso, lograron una significativa inhibición de Candida albicans con respecto al control. También observaron una liberación sostenida de plata en el tiempo, manteniendo propiedades antifúngicas. Sin embargo, el color oscuro del material nanocompósito resultante, producido por las partículas de AgNP, es claramente un aspecto desfavorable desde el punto de vista estético-odontológico. Due to the antimicrobial capacity of these particles, the possibility of modifying the acrylic prosthesis material was explored, incorporating metal nanoparticles into its polymer matrix. Kamikawa et al. evaluated the adhesion of Candida albicans and Candida glabrata on modified dental acrylics with a polymer coating coated with AgNP, observing a considerable reduction in the growth of colonies of Candida albicans (Kamikawa, Y., et al., In Vitro Antifungal Activity against Oral Candida Species Using a Denture Base Coated with Silver Nanoparticles, Journal of Nanomaterials, 2014. 2014: p. 6). In other approaches, the incorporation of AgNP into the acrylic resin has been tested. These materials would have the ability to release the active agent in a controlled manner and thus control the proliferation of microorganisms on the surface of the prosthesis. The existence of a dental prosthesis with these antimicrobial characteristics, would allow to prevent and treat stomatitis, unlike antifungal therapy that only treats the disease. Using this strategy to modify the acrylic material, (Nam KY, Lee CH, Lee CJ. Antifungal and physical characteristics of modified denture base acrylic incorporated with silver nanoparticles. Gerodontology 2012; 29 (2): e413-e9), incorporated AgNP to denture acrylics, mixing colloidal silver suspensions with acrylic, by using silver contents between 20-30% by weight, achieved a significant inhibition of Candida albicans with respect to control. They also observed a sustained release of silver over time, maintaining antifungal properties. However, the dark color of the resulting nanocomposite material, produced by AgNP particles, is clearly an unfavorable aspect from the aesthetic-dental point of view.
Por otro lado, las CuNPs han sido utilizadas para la preparación de diferentes nanocompositos poliméricos con propiedades antimicrobianas. Además, se estudiaron polímeros tales como polivinilcetona cargada con CuNP, en donde se observó la capacidad de liberar metal lentamente y de forma controlada, como también de inhibir el crecimiento de bacterias y hongos como Saccharomyces cervisiae; y la actividad antimicrobiana se correlaciona directamente con la concentración de nanopartículas (Cioffi et al.). Otros polímeros estudiados son matrices celulosas vegetales y bacterianas cargadas con nanoestructuras, tales como nanofilamentos y CuNP, mostrando acción bactericida frente a Staphylococcus aureus y Klebsiella pneunomiae. Éste polímero con la potencial aplicación para su uso en papeles para envoltorios (Theivasanthi et al.). Con respecto a polímeros acrílicos modificados con CuNP, Liu et al. (Liu, YY., Liu, DM., Chen, SY., Tung TH., Liu TY., In situ synthesis of hybrid nanocomposite with highly order arranged amoorphous metallic copper nanoparticle in poli (2- hidroxyethyl methacrylate) and its potential for blood-contact uses. Acta Biomateralia, 2008, (4), 2052-2058), incorporó CuNP en una matriz de poli(2-hidroxietil metacrilato) (pHEMA) utilizada en la fabricación de dispositivos biomédicos con aplicación cardiovascular. Los resultados muestran que la incorporación (0,03-0,15 % cobre) de CuNP reduce la adhesión plaquetaria, evitando así la producción de trombos sanguíneos, sin embargo en este trabajo no se evalúan propiedades antimicrobianas del material nanocompósito. Respecto al mecanismo antimicrobiano de los nanocompositos poliméricos/metálicos, se postula un mecanismo de liberación de iones producidos por la corrosión de las nanopartículas presentes en la matriz, debido a la difusión de moléculas de agua desde el medio externo. La difusión de moléculas de agua se ha observado incluso en matrices polímericas no polares, como el polietileno y polipropileno (Palza et al., y Ton-That, TM., Jungnickel, BJ. Water diffusion into transcrystalline layers on polypropylene. J. Appl. Polum. Sci. 1999, 74, 3275-3285). También, con el paso del tiempo, se produciría la corrosión del polímero, lo que también produciría liberación de iones, contribuyendo a la liberación sostenida de cobre en el tiempo (Palza et al.). On the other hand, CuNPs have been used for the preparation of different polymeric nanocomposites with antimicrobial properties. In addition, polymers such as CuNP-loaded polyvinyl ketone were studied, where the ability to release metal slowly and in a controlled manner was observed, as well as to inhibit the growth of bacteria and fungi such as Saccharomyces cervisiae; and the antimicrobial activity correlates directly with the concentration of nanoparticles (Cioffi et al.). Other polymers studied are plant and bacterial cellulose matrices loaded with nanostructures, such as nanofilaments and CuNP, showing bactericidal action against Staphylococcus aureus and Klebsiella pneunomiae. This polymer with the potential application for use in wrapping papers (Theivasanthi et al.). With respect to acrylic polymers modified with CuNP, Liu et al. (Liu, YY., Liu, DM., Chen, SY., Tung TH., Liu TY., In situ synthesis of hybrid nanocomposite with highly order arranged amoorphous metallic copper nanoparticle in poly (2- hydroxyethyl methacrylate) and its potential for blood-contact uses Acta Biomateralia, 2008, (4), 2052-2058), incorporated CuNP into a matrix of poly (2-hydroxyethyl methacrylate) (pHEMA) used in the manufacture of biomedical devices with cardiovascular application. The results show that the incorporation (0.03-0.15% copper) of CuNP reduces platelet adhesion, thus avoiding the production of blood thrombi, however in this work no antimicrobial properties of the nanocomposite material are evaluated. With respect to the antimicrobial mechanism of polymeric / metallic nanocomposites, a mechanism for the release of ions produced by the corrosion of the nanoparticles present in the matrix is postulated, due to the diffusion of water molecules from the external medium. The diffusion of molecules from water has been observed even in non-polar polymeric matrices, such as polyethylene and polypropylene (Palza et al., and Ton-That, TM., Jungnickel, BJ. Water diffusion into transcrystalline layers on polypropylene. J. Appl. Polum. Sci. 1999, 74, 3275-3285). Also, over time, polymer corrosion would occur, which would also produce ion release, contributing to the sustained release of copper over time (Palza et al.).
La incorporación de nanopartículas metálicas en acrílicos dentales para impartirles propiedades antimicrobianas, presentaría ventajas respecto a los antimicrobianos orgánicos tradicionales. Los antibióticos generan resistencia microbiana y efectos adversos a nivel sistémico en los pacientes, por lo que el arte previo plantea investigar nuevas alternativas antibacterianas (Nam et al.). Por otra parte, en un estudio se incorporaron clorhexidina a acrílicos dentales, encontrando que este tipo de compuestos sufre una rápida liberación en medio acuoso, además se encontró una alta liberación de monómero residual por una incompleta polimerización (Wilson, SJ1 , Wilson, HJ. The reléase of chlorhexidine from modified dental acrylic resin J Oral Rehabil. 1993 May;20(3):31 1 -9). Además, agentes dentales como clorhexidina se han estudiado en geles de metilcelulosa y ácido poliacrílico, presentando una temperatura de liberación entre 22 y 42 °C. (Musial, W., Kokol, V., Voncina, B., Deposition and reléase of chlorhexidine from non-ionic and anionic polymer matrices. Chemical Papers, 201 0 (64), 3, 346-353). En general, la incorporación de antimicrobianos orgánicos presenta un alta tasa de liberación con el aumento de la temperatura, de lo cual se puede esperar una alta pérdida del agente activo al ser usado en las condiciones de termopolimerización del acrílico de prótesis (temperaturas mayor a 90°C, bajo presión). Estos aspectos de estabilidad del agente antimicrobiano bajo las condiciones de termocurado podrían ser mejorados al utilizar nanopartículas metálicas, como las de cobre. The incorporation of metal nanoparticles in dental acrylics to impart antimicrobial properties, would have advantages over traditional organic antimicrobials. Antibiotics generate microbial resistance and adverse effects at the systemic level in patients, so the prior art suggests investigating new antibacterial alternatives (Nam et al.). On the other hand, in a study chlorhexidine was incorporated into dental acrylics, finding that this type of compounds undergoes rapid release in aqueous medium, in addition a high release of residual monomer was found by incomplete polymerization (Wilson, SJ1, Wilson, HJ. The relée of chlorhexidine from modified dental acrylic resin J Oral Rehabil. 1993 May; 20 (3): 31 1-9). In addition, dental agents such as chlorhexidine have been studied in methylcellulose and polyacrylic acid gels, presenting a release temperature between 22 and 42 ° C. (Musial, W., Kokol, V., Voncina, B., Deposition and relée of chlorhexidine from non-ionic and anionic polymer matrices. Chemical Papers, 201 0 (64), 3, 346-353). In general, the incorporation of organic antimicrobials presents a high release rate with increasing temperature, from which a high loss of the active agent can be expected when used in the thermopolymerization conditions of the prosthetic acrylic (temperatures greater than 90 ° C, under pressure). These aspects of stability of the antimicrobial agent under thermosetting conditions could be improved by using metal nanoparticles, such as copper.
Es de conocimiento que la cavidad bucal es un tipo de hábitat donde viven un conjunto de microorganismos (comunidad microbiana). En donde la manifestación de las caries dentales está mediada por mecanismos complejos que son iniciados por factores, entre los que se incluyen genéticos, conductuales, ambientales y microbianos. En el caso de los factores microbianos, la presencia de patógenos es fundamental para el inicio y progresión de las lesiones de caries, sin bacterias no existe lesión. De hecho se trata de una enfermedad infecciosa polimicrobiana, en donde cada especie bacteriana individual puede contribuir colectivamente a la cariogenicidad total de la biocomunidad de la placa dental (biopelícula dental) asociada a caries. Las fuentes intrínsecas de nutrientes para los microorganismos de la cavidad bucal son los materiales que se encuentran en torno de los dientes, los exudados, las células epiteliales degradadas y los componentes de la saliva, ciertas proteínas salivales proporcionan aminoácidos que influyen en el crecimiento de Streptococcus mutans y de Streptococcus sanguis; la saliva de los sujetos con caries influye mejor en el crecimiento de los Streptococcus mutans. Además la comida que ingerimos permanece en la cavidad bucal, sirve como fuente extrínseca de nutrientes para la microflora bucal. It is known that the oral cavity is a type of habitat where a group of microorganisms (microbial community) live. Where the manifestation of dental caries is mediated by complex mechanisms that are initiated by factors, including genetic, behavioral, environmental and microbial. In the case of microbial factors, the presence of pathogens is essential for the onset and progression of caries lesions, without bacteria there is no injury. In fact, it is a polymicrobial infectious disease, where each individual bacterial species can collectively contribute to the total cariogenicity of the dental plaque bio-community (dental biofilm) associated with caries. The intrinsic sources of nutrients for microorganisms of the oral cavity are the materials that are around the teeth, exudates, degraded epithelial cells and components of saliva, certain salivary proteins provide amino acids that influence the growth of Streptococcus mutans and Streptococcus sanguis; The saliva of caries subjects has a better influence on the growth of Streptococcus mutans. In addition, the food we eat remains in the oral cavity, serving as an extrinsic source of nutrients for the oral microflora.
La caries dental es una enfermedad infecciosa de etiología multifactorial, donde los microorganismos organizados en una biopelícula, denominada placa dental, constituyen un factor determinante en el desarrollo de la lesión de caries, y esta representa el signo tardío de la enfermedad. En cada etapa de progresión de la lesión predominan especies microbianas, como resultado de una sucesión de microorganismos. En el caso de sujetos sanos libres de caries se ha podido observar el predominio de microorganismos distintos a aquellos asociados con la enfermedad, tal como Streptococcus sanguinis. Sin embargo, en sujetos afectados por la caries dental los estreptococos pertenecientes al grupo mutans han sido los preponderantes durante el inicio y progresión de la lesión, especialmente Streptococcus mutans, mientras que Lactobacillus y Bifidobacterium predominan en las etapas avanzadas de la lesión. Dental caries is an infectious disease of multifactorial etiology, where microorganisms organized in a biofilm, called dental plaque, are a determining factor in the development of caries lesions, and this represents the late sign of the disease. At each stage of progression of the lesion, microbial species predominate, as a result of a succession of microorganisms. In the case of healthy caries-free subjects, the predominance of microorganisms other than those associated with the disease, such as Streptococcus sanguinis, has been observed. However, in subjects affected by dental caries, the streptococci belonging to the mutans group have been the predominant during the onset and progression of the lesion, especially Streptococcus mutans, while Lactobacillus and Bifidobacterium predominate in the advanced stages of the lesion.
Otro tipo de enfermedad microbiana que afecta a los tejidos orales, está relacionada con el microorganismo Candida albicans, el cual es una especie de levadura que causa la estomatitis subprótesica que es causada por el uso de una prótesis dental; y generalmente dicho microorganismo se desarrolla debido a un ajuste escaso de dicha prótesis o a una limpieza escasa de la misma. La estomatitis subprótesica relacionada con C. albicans es una reacción inflamatoria no específica a los antígenos, las toxinas y las enzimas microbianos que son producidos por los microorganismos colonizadores, la cual es una sería infección de la mucosa oral, es una enfermedad común y periódica que afecta hasta 67% de los usuarios de prótesis dental. Es sabido que factores, tal como la higiene oral deficiente, alta ingesta de carbohidrato, flujo salival reducido, uso continuo de la prótesis, envejecimiento, desnutrición, supresión inmunológica, radioterapia, diabetes mellitus y posiblemente tratamiento con antibióticos, aumentan la susceptibilidad a la C. albicans. Another type of microbial disease that affects oral tissues is related to the microorganism Candida albicans, which is a species of yeast that causes subprottic stomatitis that is caused by the use of a dental prosthesis; and generally said microorganism develops due to poor adjustment of said prosthesis or poor cleaning thereof. Subprothetic stomatitis related to C. albicans is a non-specific inflammatory reaction to the antigens, toxins and microbial enzymes that are produced by the colonizing microorganisms, which is an infection of the oral mucosa, is a common and periodic disease that affects up to 67% of prosthesis users dental. It is known that factors, such as poor oral hygiene, high carbohydrate intake, reduced salivary flow, continuous use of the prosthesis, aging, malnutrition, immune suppression, radiation therapy, diabetes mellitus and possibly antibiotic treatment, increase susceptibility to C albicans
Los biomateriales pueden ser de origen artificial o biológico. En el primer caso podemos mencionar a los materiales metálicos, poliméricos y cerámicos. Los implantes metálicos, junto con sus aleaciones, son los más utilizados para implantes ortopédicos (clavos, alambres, placas) e implantes dentales (tornillos), ya que deben poseer una gran resistencia al desgaste mecánico y ser capaces de soportar la carga adecuada para su función. Los metales usados para la fabricación de estos implantes son: acero inoxidable, aleaciones de cobalto con cromo, molibdeno y níquel, titanio puro (Ti) y sus aleaciones con aluminio y vanadio. Con respecto a los biomateriales biológicos, se pueden nombrar por ejemplo fragmentos de huesos, injertos de piel, matriz extracelular hasta células madres (humana o animal). Biomaterials can be of artificial or biological origin. In the first case we can mention the metallic, polymeric and ceramic materials. Metal implants, together with their alloys, are the most commonly used for orthopedic implants (nails, wires, plates) and dental implants (screws), since they must have a high resistance to mechanical wear and be able to withstand the appropriate load for their function. The metals used to manufacture these implants are: stainless steel, cobalt alloys with chromium, molybdenum and nickel, pure titanium (Ti) and their alloys with aluminum and vanadium. With respect to biological biomaterials, bone fragments, skin grafts, extracellular matrix to stem cells (human or animal) can be named, for example.
Actualmente, con el advenimiento de la nanotecnología se han desarrollado ciertos nanomateriales, en particular nanopartículas (NPs) inorgánicas, que presentan un marcado efecto microbicida sobre una amplia variedad de microorganismos, tales como virus, bacterias y hongos. La capacidad microbicida de las NPs está vinculada a la naturaleza del material y a ciertas características intrínsecas de las mismas, como sus dimensiones nanómetricas (lo cual les permite ser internalizadas con mayor facilidad en microorganismos) y la alta relación área/volumen que permite un mayor contacto e interacción con dichos microorganismos. Entre las NPs metálicas que han demostrado tener propiedades microbicidas las más importantes son las de plata, óxido de zinc, cobre u óxidos de hierro. Las primeras tres sustancias ya presentan esta propiedad en su forma macroscópica, mientras que los óxidos de hierro únicamente resultan ser microbicidas en forma nanoestructurada. Las NPs presentan mecanismos de acción microbicida totalmente diferentes a los antibióticos tradicionales, proporcionando así una alternativa promisoria. Los mecanismos de acción bactericida de las NPs metálicas no han sido completamente dilucidados, aunque se han postulado varios tipos de mecanismos. Entre los cuales, se pueden mencionar perturbaciones en las funciones de la membrana celular (las cuales alteran la permeabilidad y la respiración celular), el ingreso de las nanopartículas a la célula, lo que genera una alteración en las funciones de las proteínas y el ADN, o la producción de especies oxidativas debido a la presencia de NPs en el interior de la célula. No es sencillo realizar un análisis comparativo de los datos de la bibliografía ya que la acción bactericida dependerá de una amplia variedad de factores entre los que se pueden mencionar: el tamaño y la forma de las NPs, su composición química, el recubrimiento y su carga superficial potencial y la concentración de NPs usada. Currently, with the advent of nanotechnology, certain nanomaterials have been developed, in particular inorganic nanoparticles (NPs), which have a marked microbicidal effect on a wide variety of microorganisms, such as viruses, bacteria and fungi. The microbicidal capacity of NPs is linked to the nature of the material and to certain intrinsic characteristics of them, such as their nanometric dimensions (which allows them to be more easily internalized in microorganisms) and the high area / volume ratio that allows greater contact. and interaction with these microorganisms. Among the metallic NPs that have been shown to have microbicidal properties, the most important are those of silver, zinc oxide, copper or iron oxides. The first three substances already have this property in their macroscopic form, while iron oxides only turn out to be microbicides in a nanostructured form. NPs have mechanisms of microbicidal action that are totally different from traditional antibiotics, thus providing a promising alternative. The bactericidal action mechanisms of metallic NPs have not been fully elucidated, although several types of mechanisms have been postulated. Among which, disturbances in the functions of the cell membrane (which alter permeability and cellular respiration), the entry of nanoparticles into the cell, which causes an alteration in the functions of proteins and DNA, or the production of oxidative species due to the presence of NPs inside the cell. It is not easy to carry out a comparative analysis of the data in the literature since the bactericidal action will depend on a wide variety of factors, among which we can mention: the size and shape of the NPs, their chemical composition, the coating and their load surface potential and the concentration of NPs used.
La preparación de dicho material dental se basa en la incorporación de nanopartículas de cobre (CuNPs) al material mediante su formación in-situ a partir de un precursor de cobre o mediante su adición directa previa síntesis. La ventaja de esta tecnología radica en el hecho que no se altera el proceso comercial utilizado actualmente para la producción de las prótesis, dado que se basa en la misma resina utilizada actualmente sin alterarla. Estos nuevos dispositivos protésicos con tecnología de nanopartículas de cobre, presentarían propiedades antifúngicas que permitirían prevenir y/o tratar la estomatitis subprotésica así como reducir la cantidad de bacterias cariogénicas en los usuarios con prótesis dentales. En resumen, la tecnología que se propone para la elaboración del material de prótesis antimicrobiana, considera la síntesis y/o incorporación de las CuNPs durante el proceso de preparación de las prótesis que actualmente se comercializa lo que facilitaría la penetración de nuestra metodología al mercado. The preparation of said dental material is based on the incorporation of copper nanoparticles (CuNPs) into the material by in-situ formation from a copper precursor or by direct addition prior synthesis. The advantage of this technology lies in the fact that the commercial process currently used for the production of the prostheses is not altered, since it is based on the same resin currently used without altering it. These new prosthetic devices with copper nanoparticle technology, would have antifungal properties that would prevent and / or treat subprothetic stomatitis as well as reduce the amount of cariogenic bacteria in users with dental prostheses. In summary, the technology proposed for the preparation of the antimicrobial prosthesis material, considers the synthesis and / or incorporation of the CuNPs during the process of preparation of the prostheses that are currently marketed, which would facilitate the penetration of our methodology to the market.
Se han realizado diversos esfuerzos para proporcionar una acción antimicrobiana a dispositivos y materiales dentales, de los cuales podemos citar: Various efforts have been made to provide an antimicrobial action to dental devices and materials, of which we can cite:
El documento RU 2444349 describe una composición adhesiva modificada para fijación de la dentadura, la cual contiene porcentaje en peso de: polivinilpirrolidona-5, ácido poliacrílico -15, glicerol-4, cetrimida antiséptico; alginato de sodio-5, abeto balsámico-10, nanopartículas de plata de tamaño de 1 a 5 nm, y el resto agua destilada. La simplicidad, seguridad y eficacia de la composición de adhesivo modificado desarrollado para la fijación de la dentadura permite utilizarla en la práctica ortopédica común, en donde la composición de adhesivo proporciona considerable reducción de una longitud de adaptación del pacientes sin dentadura con prótesis total, no causa ninguna acción tóxica sobre los tejidos de área y el cuerpo de soporte de la prótesis en su conjunto y muestra propiedades adhesivas óptimas, permaneciendo sin resolver por un largo tiempo con la Ingesta de comida callente. RU 2444349 describes a modified adhesive composition for denture fixation, which contains a percentage by weight of: polyvinylpyrrolidone-5, polyacrylic acid -15, glycerol-4, antiseptic cetrimide; Sodium alginate-5, balsamic fir-10, silver nanoparticles of 1 to 5 nm size, and the rest distilled water. The simplicity, safety and efficacy of the modified adhesive composition developed for the fixation of the denture allows it to be used in common orthopedic practice, where the adhesive composition provides considerable reduction of an adaptation length of dentureless patients with prostheses. In total, it does not cause any toxic action on the area tissues and the support body of the prosthesis as a whole and shows optimal adhesive properties, remaining unresolved for a long time with the intake of warm food.
El documento US 2013014671 describe un material dental antlmicroblano que se caracteriza por la adición de aproximadamente 0,1 a 0,5% en peso de partículas metálicas antibacterlanas a un óxido de circonio (Zr02) como un sustrato de polvo de material dental antlmicroblano. El material metálico posee excelentes propiedades antlbacterianas que liberan iones, los cuales Incluyen: plata, oro, platino, paladlo, iridio, titanio, cobre, estaño, antimonio, bismuto y zinc, especialmente se prefiere utilizar plata, cobre y titanio. Después de estar completamente mezclado y slnterizado a partir de las partículas metálicas antibacterlanas se difunde de forma natural en el sustrato de óxido de circonio, de modo que se dispone de un material dental antlmicroblana para implantes de prótesis dentales o prótesis o cualquier otra reconstrucción oral. US 2013014671 describes an antlmicroblane dental material characterized by the addition of about 0.1 to 0.5% by weight of antibacterial metal particles to a zirconium oxide (Zr0 2 ) as a powder substrate of antlmicroblane dental material. The metallic material possesses excellent antlbacterial properties that release ions, which include: silver, gold, platinum, palladium, iridium, titanium, copper, tin, antimony, bismuth and zinc, especially it is preferred to use silver, copper and titanium. After being completely mixed and screened from the antibacterial metal particles it diffuses naturally in the zirconium oxide substrate, so that an antlmicroblane dental material is available for implants of dentures or prostheses or any other oral reconstruction.
El documento US 6267590 describe un aparato dental, tal como del tipo de ortodoncia, para ser colocado en la boca y que tiene un agente antimlcrobiano Inorgánico sobre una superficie, en donde el agente es preferiblemente una zeollta. El aparato dental puede comprender metal o un polímero (pollcarbonato) y el agente puede estar presente en un recubrimiento que se aplica a las superficies del aparato para ser contactado por líquidos o sólidos en la boca. El aparato puede ser de una resina pollmérica o un elastómero que Incorpora el agente. Un agente antlmicroblano preferido es partículas de cerámica (por ejemplo, partículas de zeollta) que contienen iones metálicos antimlcrobianos, por ejemplo, Iones de plata, como el agente activo. US 6267590 describes a dental apparatus, such as orthodontic type, to be placed in the mouth and having an inorganic antimlcrobial agent on a surface, wherein the agent is preferably a zeollta. The dental apparatus may comprise metal or a polymer (polycarbonate) and the agent may be present in a coating that is applied to the surfaces of the apparatus to be contacted by liquids or solids in the mouth. The apparatus can be of a polymeric resin or an elastomer that incorporates the agent. A preferred antlmicroblane agent is ceramic particles (for example, zeollta particles) containing antimlcrobial metal ions, for example, silver ions, as the active agent.
El documento US 3.476.854 describe una formulación de un material acríllco (metacrilatos de alquilo), resinas de slllcona, copolímeros de vlnilo, y pollamida para formar revestimientos o acondicionadores de tejidos para dentaduras postizas, cargado con compuestos antifúnglcos de carboxilatos de zinc (undecilenato), el cual se dispersa en dicha resina, en donde dicho agente antlfúngico se selecciona desde sales de metales pesados de ácidos grasos monocarboxíllcos, hasta ácidos grasos de longitud de cadena media, ácido benzoico, benzoato de bencilo, ácido salicílico, y salicilato de bencilo, y estando dicho agente antifúngico presente en dicha resina en una cantidad eficaz para retardar el crecimiento de hongos en dicha composición, y siendo dicha cantidad al menos aproximadamente al 1 % en peso de dicha composición. US 3,476,854 discloses a formulation of an acrylic material (alkyl methacrylates), slllcona resins, vlnyl copolymers, and polylamide to form coatings or conditioners for dentures, loaded with antifungal compounds of zinc carboxylates (undecylenate) ), which is dispersed in said resin, wherein said antlfungal agent is selected from heavy metal salts of monocarboxylic fatty acids, to medium chain length fatty acids, benzoic acid, benzoate of benzyl, salicylic acid, and benzyl salicylate, and said antifungal agent being present in said resin in an amount effective to retard fungal growth in said composition, and said amount being at least about 1% by weight of said composition.
El documento EP 2536379 A2 describe una prótesis dental antibacteriana que comprende un sustrato polimérico con un componente de polimérico funcional y un agente antimicótico liberable y el cual se encuentra unido al componente polimérico funcional de tal manera que el agente antifúngico se eluya lentamente desde el componente polimérico funcional durante un período prolongado de tiempo. EP 2536379 A2 describes an antibacterial dental prosthesis comprising a polymeric substrate with a functional polymer component and a releasable antifungal agent and which is attached to the functional polymer component such that the antifungal agent is slowly eluted from the polymer component. functional for a prolonged period of time.
El documento EP 0081962 A2 describe una composición sólida comprimida para la limpieza de prótesis dentales que es muy efervescente cuando se añade al agua, la cual está compuesta por una mezcla de perborato, dicloroisocianurato y un álcali, lo cual produce una solución de limpieza de pH 1 1 . EP 0081962 A2 describes a compressed solid composition for cleaning dentures that is very effervescent when added to water, which is composed of a mixture of perborate, dichloroisocyanurate and an alkali, which produces a pH cleaning solution. eleven .
El documento EP 0400080 B1 describe un método para proporcionar una prótesis dental con un revestimiento protector, el cual comprende aplicar a dicha prótesis una dispersión acuosa de un recubrimiento de un polisacárido no tóxico, antibacteriano para prótesis, el cual reduce la adhesión de células Streptococcus salivarius para prótesis de resina acrílica por al menos 25% en comparación con un control sin revestí. EP 0400080 B1 describes a method of providing a dental prosthesis with a protective coating, which comprises applying to said prosthesis an aqueous dispersion of a coating of a non-toxic, antibacterial prosthesis polysaccharide, which reduces the adhesion of Streptococcus salivarius cells for acrylic resin prostheses by at least 25% compared to an uncoated control.
El documento EP 1 003791 A4 describe una formulación de una crema limpiadora adhesiva y antimicrobiana para prótesis dental, la cual comprende nistatina o una combinación de 8- hidroxiquinolina (o su sal) y al menos una sal de cobre (II), en donde dicha formulación es para evitar la estomatitis protésica mediante la inhibición de Candida albicans.  EP 1 003791 A4 describes a formulation of an adhesive and antimicrobial cleansing cream for dental prostheses, which comprises nystatin or a combination of 8-hydroxyquinoline (or its salt) and at least one copper (II) salt, wherein said formulation is to prevent prosthetic stomatitis by inhibiting Candida albicans.
El documento US 4.332.791 describe una composición acuosa para pasta dental que contiene al menos un compuesto de cobre soluble en agua y al menos un agente de pulido, la mayor parte de dicho agente de pulido es dióxido de silicio. El documento EP 0471396 describe una composición oral que comprende una sal de bicarbonato, un compuesto de cobre presente en una cantidad eficaz para inhibir el crecimiento bacteriano y un agente complejante presente en una cantidad eficaz para estabilizar el compuesto de cobre. US 4,332,791 describes an aqueous toothpaste composition containing at least one water soluble copper compound and at least one polishing agent, the majority of said polishing agent is silicon dioxide. EP 0471396 describes an oral composition comprising a bicarbonate salt, a copper compound present in an amount effective to inhibit bacterial growth and a complexing agent present in an amount effective to stabilize the copper compound.
El documento US 201 1 /0229534 A1 , describe form u laciones para el cuidado oral que comprende u na cantidad anti -i rritante de u na sal de sal ici lato y u na cantidad eficaz de u n agente potenciador de sabor, además de una cantidad anti -inflamatoria de un agente irritante , por ejemplo ketorolac. Dic ha form u laciones para el cuidado bucal pueden util izarse en diversos dispositivos para tratar y/o preven i r la i rritación de las m ucosas tales como u lceraciones . US 201 1/0229534 A1, describes oral care forms comprising an anti-irritant amount of an icylate salt salt and an effective amount of a flavor enhancing agent, in addition to an anti amount -inflammatory of an irritant, for example ketorolac. Such oral care formulations can be used in various devices to treat and / or prevent the irritation of mucous membranes such as ulcerations.
El documento US 9034354 B2 describe recubrimientos de superficie antibacterianas y antimicrobianas y materiales dentales mediante la utilización de las propiedades antimicrobianas de calcogénuro de cobre y/o haluro de cobre (CuQ, donde Q = calcógenos que incluye oxígeno, o halógenos, o nada). En donde una barrera antimicrobiana se crea mediante la incorporación de nanopartículas CuQ de un tamaño adecuado y a una concentración necesaria y suficiente para crear un entorno bioeléctrico único. Los resultados del entorno bioeléctrico único en eficacia biocida es a través de un mecanismo de multi-factorial que comprenden una combinación del flujo cuántico intrínseco de iones de cobre (Cu0, Cu1 +, Cu2+) y el fregadero de electrones de alta de superficie a volumen facilitadas por la nanopartículas. El resultado es el flujo constante cuántico de cobre que se manifiesta y establece el entorno antimicrobiano para prevenir o inhibir el crecimiento de bacterias. La presencia de CuQ resulta en la inhibición o el retraso de la destrucción bacteriana y la descomposición enzimática endógena de la zona de resina inter-difusión, la integridad de los cuales es esencial para la longevidad de la restauración dental. Es así como, dicha invención se encuentra dirigida a un adhesivo bacteriostático/bactericida y anti-colagenolítico que se utiliza para controlar la invasión y proliferación de microorganismos. En relación al uso de cobre para el control de la estomatitis subprotésica, el documento EP 1003791 A4 describe una formulación de una crema adhesiva antimicrobiana para prótesis dentales, en donde el principio activo del adhesivo consiste de 8-hidroxiquinolina (0,0001 -0,5%) y de una sal de cobre II (0,001 -0,3%) es aquel que produce mayor actividad frente a C. albicans mediante ensayos in vitro. US 9034354 B2 describes antibacterial and antimicrobial surface coatings and dental materials by utilizing the antimicrobial properties of copper chalcogenide and / or copper halide (CuQ, where Q = chalcogens including oxygen, or halogens, or nothing). Where an antimicrobial barrier is created by incorporating CuQ nanoparticles of an adequate size and at a concentration necessary and sufficient to create a unique bioelectric environment. The results of the unique bioelectric environment in biocidal efficiency is through a multi-factor mechanism that comprises a combination of the intrinsic quantum flow of copper ions (Cu 0 , Cu 1 + , Cu 2+ ) and the high electron sink from surface to volume facilitated by the nanoparticles. The result is the constant quantum flow of copper that manifests and establishes the antimicrobial environment to prevent or inhibit the growth of bacteria. The presence of CuQ results in the inhibition or delay of bacterial destruction and endogenous enzymatic decomposition of the inter-diffusion resin zone, the integrity of which is essential for the longevity of dental restoration. Thus, said invention is directed to a bacteriostatic / bactericidal and anti-collagenolytic adhesive that is used to control the invasion and proliferation of microorganisms. In relation to the use of copper for the control of subprothetic stomatitis, EP 1003791 A4 describes a formulation of an antimicrobial adhesive cream for dental prostheses, wherein the active principle of the adhesive consists of 8-hydroxyquinoline (0.0001-0, 5%) and a copper salt II (0.001 -0.3%) is the one that produces the most activity against C. albicans through in vitro assays.
El cobre también aparece como agente activo en la formulación de pastas dentales con propiedades para el control de placa microbiana. Es así como, el documento US 4.332.791 describe una pasta dental que contiene sílice y una sal de cobre (0,001 -5%) como componentes activos, mientras que en el documento EP 0471396 A1 , la fracción activa consiste de una sal de cobre (0,01 -5%), bicarbonato de sodio y de una alquilamina que actúa como estabilizante del ion metálico. También se han utilizado sales como el salicilato de cobre (0,05-0,3%), en la formulación de colutorios para el control de úlceras e irritaciones orales, tal como se describe en el documento US 201 1 /0229534 A1 . Copper also appears as an active agent in the formulation of toothpastes with properties for the control of microbial plaque. Thus, US 4,332,791 describes a toothpaste containing silica and a copper salt (0.001-5%) as active components, while in EP 0471396 A1, the active fraction consists of a copper salt (0.01-5%), sodium bicarbonate and an alkylamine that acts as a metal ion stabilizer. Salts such as copper salicylate (0.05-0.3%) have also been used in the formulation of mouthwashes for the control of oral ulcers and irritations, as described in US 201 1/0229534 A1.
La mayoría de los materiales dentales actualmente utilizados para la preparación de restauraciones, implantes, elementos ortodónticos, prótesis y otros; no poseen propiedades antimicrobianas que permitan controlar la actividad de los microorganismos en la cavidad oral. Por lo cual, el estado de la técnica no describen la preparación de prótesis dentales a base de acrílico (PMMA) con cobre, utilizando este elemento como aditivo antimicrobiano, ya sea en forma de sal ó de nanopartícula. Tampoco se detectó la formulación de productos ó materiales dentales, así como de terapias de salud oral utilizando cobre como nanopartícula. Most of the dental materials currently used for the preparation of restorations, implants, orthodontic elements, prostheses and others; they do not possess antimicrobial properties that allow the control of the activity of microorganisms in the oral cavity. Therefore, the state of the art does not describe the preparation of dentures based on acrylic (PMMA) with copper, using this element as an antimicrobial additive, either in the form of salt or nanoparticle. Nor was the formulation of dental products or materials, as well as oral health therapies using copper as a nanoparticle.
DESCRIPCIÓN DETALLADA DE LA INVENCIÓN. DETAILED DESCRIPTION OF THE INVENTION.
La presente invención se encuentra orientada al desarrollo de un nuevo material para la fabricación de un dispositivo de prótesis dental con propiedades antimicrobianas, en forma preferente para prevenir la estomatitis subprotésica provocada por el patógeno Candida albicans, y la reducción de bacterias como Streptococcus mutans, patógeno responsable por el inicio y progresión de la formación de caries. Además, de una forma preferente se describe la síntesis del material antimicrobiano para prótesis utilizando nanopartículas de cobre como agente antifúngico a través de la incorporación de nanopartículas de cobre dentro de una resina acrílica de termocurado, la cual permite generar un material de prótesis con propiedades antimicrobianas especialmente frente Candida albicans y particularmente frente a Streptococcus mutans, de tal manera de mantener las propiedades mecánicas, de color y de citocompatibilidad. The present invention is oriented to the development of a new material for the manufacture of a dental prosthesis device with antimicrobial properties, preferably to prevent subprothetic stomatitis caused by the Candida pathogen albicans, and the reduction of bacteria such as Streptococcus mutans, a pathogen responsible for the onset and progression of tooth decay. In addition, the synthesis of the antimicrobial material for prostheses using copper nanoparticles as an antifungal agent is described in a preferred manner through the incorporation of copper nanoparticles into an acrylic thermosetting resin, which allows the generation of a prosthetic material with antimicrobial properties. especially against Candida albicans and particularly against Streptococcus mutans, in such a way to maintain the mechanical, color and cytocompatibility properties.
En una realización preferida, la presente invención proporciona un material de prótesis dental nanocompósito CuNP/PMMA antimicrobiano a base de nanopartículas de cobre (CuNP) y polimetilmetacrilato (PMMA), que comprende las CuNP dispersas en dicha resina y formadas in situ durante el proceso de termopolimerizacion a partir de una sal de cobre como precursor. In a preferred embodiment, the present invention provides an antimicrobial CuNP / PMMA nanocomposite dental prosthesis material based on copper nanoparticles (CuNP) and polymethylmethacrylate (PMMA), comprising CuNP dispersed in said resin and formed in situ during the process of thermopolymerization from a copper salt as a precursor.
En otras realizaciones preferidas, la presente invención proporciona un material nanocompósito que incluye CuNP/PMMA de termopolimerizacion a base de nanopartículas de cobre (CuNP) y polimetilmetacrilato (PMMA); en donde las aplicaciones de dicho material nanocompósito (polímeros acrílicos con CuNP) son realizadas en: prótesis dental removible o fija; resinas de restauración dental; adhesivo de resina (adhesivo para unir la resina de restauración al diente), sellante de fosas y fisuras (sellante acrílico que se usa para prevenir el desarrollo de una caries a partir de fisuras menores en los dientes, ampliamente usados en niños), adhesivo ortodóncico (utilizado para adherir el bracket sobre la superficie del diente), vidrio ionómero (un material versátil en odontología, que puede ser usado como una restauración, temporal en adultos o permanente en niños, o como agente cementante de otros materiales dentales) y cemento óseo o quirúrgico (acrílico de autocurado que se usa para la fijación de prótesis ortopédicas con el hueso o en craneoplastías). In other preferred embodiments, the present invention provides a nanocomposite material that includes copper nanoparticles (CuNP) and polymethylmethacrylate (PMMA) thermopolymerization CuNP / PMMA; wherein the applications of said nanocomposite material (acrylic polymers with CuNP) are made in: removable or fixed dental prostheses; dental restoration resins; resin adhesive (adhesive to bond the restoration resin to the tooth), pit and fissure sealant (acrylic sealant used to prevent the development of caries from minor fissures in the teeth, widely used in children), orthodontic adhesive (used to adhere the bracket on the surface of the tooth), ionomer glass (a versatile material in dentistry, which can be used as a restoration, temporary in adults or permanent in children, or as a cementing agent of other dental materials) and bone cement or surgical (self-curing acrylic used to fix orthopedic prostheses with bone or cranioplasty).
En otra realización preferida, la presente invención comprende un sellante dental antimicrobiano que comprende un sellante dental; y una resina dental antimicrobiana que incluye una cantidad antimicrobiana de nanopartículas de cobre (CuNP) difundido en el mismo. En otra forma de realización preferida, la invención proporciona un método para prevenir caries dentales secundarias incluyendo la aplicación de una resina dental de restauración nanocompósita a base de nanopartículas de cobre (CuNP). In another preferred embodiment, the present invention comprises an antimicrobial dental sealant comprising a dental sealant; and an antimicrobial dental resin that includes an antimicrobial amount of copper nanoparticles (CuNP) diffused therein. In another preferred embodiment, the invention provides a method for preventing secondary dental caries including the application of a nanocomposite restorative dental resin based on copper nanoparticles (CuNP).
En otra realización preferida, la invención proporciona un método para prevenir o inhibir la caries dental que comprende aplicar un sellante dental antimicrobiano sobre fosas y fisuras de un diente, en donde el sellador antimicrobiano incluye una resina dental antimicrobiana que incluye una cantidad antimicrobiana de nanopartículas de cobre (CuNP) difundido en el mismo. In another preferred embodiment, the invention provides a method for preventing or inhibiting tooth decay which comprises applying an antimicrobial dental sealant to pits and fissures of a tooth, wherein the antimicrobial sealant includes an antimicrobial dental resin that includes an antimicrobial amount of nanoparticles of copper (CuNP) diffused in it.
En otra realización preferida, la presente invención proporciona un método para inhibir o limitar el crecimiento microbiano en el área de esmalte en contacto con bracket ortodoncicos que comprende el uso de un adhesivo ortodoncico antimicrobiano de nanopartículas de cobre (CuNP) difundido en el mismo. In another preferred embodiment, the present invention provides a method for inhibiting or limiting microbial growth in the area of enamel in contact with orthodontic brackets comprising the use of an orthodontic copper nanoparticle orthodontic adhesive (CuNP) diffused therein.
Cabe señalar que en cada una de las realizaciones preferidas, las nanopartículas de cobre (CuNP) poseen un tamaño de partículas de cobre de entre 40 a 100 nm. It should be noted that in each of the preferred embodiments, the copper nanoparticles (CuNP) have a copper particle size of between 40 to 100 nm.
La existencia de una prótesis dental con estas propiedades antimicrobianas, permitiría prevenir la estomatitis subprotésica y la formación de caries. A diferencia de la actual terapia antimicótica orientada a tratar la enfermedad, el uso de una prótesis antifúngica tendría el doble efecto de prevenir y tratar dichas patologías. Las propiedades antifungicas del nuevo material de prótesis a base de nanopartículas de cobre, controlaría la proliferación de los microorganismos en la superficie de la prótesis, matando las colonias del patógeno (efecto fungicida) así como reduciendo su adhesión en la superficie de la prótesis (efecto antifouling). Estas condiciones antimicrobianas provistas por el nuevo material de prótesis, deberían reducir considerablemente las posibilidades de manifestar dichas patologías. Adicionalmente, los usuarios que manifiesten la patología podrían reemplazar la prótesis dental convencional por el dispositivo antimicrobiano, lo cual constituiría una nueva alternativa de tratamiento de la estomatitis subprotésica sin los inconvenientes causados por la terapia antimicótica tradicional. La prevención de la estomatitis subprotésica, mejoraría considerablemente la calidad de vida de los usuarios de prótesis, así como evitaría que los pacientes inviertan en gastos y tiempo extra que implica el tratamiento odontológico de la patología. Particularmente, tendría un significativo impacto social en la salud oral de la alta población de adultos mayores; así como en los estratos socioeconómicos más vulnerables que utilizan la prótesis removible como la única alternativa de rehabilitación dental. The existence of a dental prosthesis with these antimicrobial properties, would allow to prevent subprothetic stomatitis and caries formation. Unlike the current antifungal therapy aimed at treating the disease, the use of an antifungal prosthesis would have the double effect of preventing and treating such pathologies. The antifungal properties of the new prosthetic material based on copper nanoparticles, would control the proliferation of microorganisms on the surface of the prosthesis, killing the colonies of the pathogen (fungicidal effect) as well as reducing their adhesion on the surface of the prosthesis (effect antifouling) These antimicrobial conditions provided by the new prosthetic material should considerably reduce the chances of manifesting these pathologies. Additionally, users who manifest the pathology could replace the conventional dental prosthesis with the antimicrobial device, which would constitute a new alternative for the treatment of subprothetic stomatitis without the inconvenience caused by traditional antifungal therapy. The prevention of subprosthetic stomatitis, would significantly improve the quality of life of prosthesis users, as well as prevent patients from investing in expenses and extra time involved in the dental treatment of the pathology. In particular, it would have a significant social impact on the oral health of the high population of older adults; as well as in the most vulnerable socioeconomic strata that use the removable prosthesis as the only alternative for dental rehabilitation.
La prótesis removible es actualmente la alternativa más usada en la rehabilitación de pacientes parcial o totalmente desdentados, especialmente en grupos de escasos recursos, y es la principal forma de rehabilitación dental en los servicios de atención primaria del país. A nivel mundial, este tipo de implementos se ve generalizado en toda la población en un alto porcentaje. Es así como, en países como Holanda el 1 9% de la población mayor de 16 años usa prótesis [Central Bureau of Statistics (Statistics Netherlands), Web magazine, 28 December 2005], en España se estiman 9 millones de usuarios (20 % de la población) [U&N AC Nielsen, Análisis de Mercados, El Blog de la Salud Bucal (Dentaid), http://www.blogsaludbucal.eS/archive/2010/10/25/protesis-dentales-comodas-y-limpias.html (2009)], mientras que en Estados Unidos más de 35 millones de personas usan prótesis totales o parciales [The National Center for Health Care Statistics http://www.cdc.qov/nchs/)1. En Chile, el uso de prótesis dental aparece en el 50% de los planes del "Flujograma de Tratamiento Odontológico para adultos de 60 años" de la "Guía Clínica de Salud Oral Integral para Adultos de 60 años" del MINSAL (2010). Datos de la "Encuesta Nacional de Salud" realizada el 2003, indican que más del 60% de la población mayor de 65 años es usuaria de prótesis dentales. The removable prosthesis is currently the most widely used alternative in the rehabilitation of partially or totally toothless patients, especially in low-income groups, and is the main form of dental rehabilitation in the country's primary care services. Worldwide, this type of implements is widespread in the entire population in a high percentage. Thus, in countries like Holland, 1 9% of the population over 16 years of age uses prostheses [Central Bureau of Statistics (Statistics Netherlands), Web magazine, December 28, 2005], in Spain 9 million users are estimated (20% of the population) [U&N AC Nielsen, Market Analysis, The Oral Health Blog (Dentaid), http://www.blogsaludbucal.eS/archive/2010/10/25/protesis-dentales-comodas-y-limpias .html (2009)], while in the United States more than 35 million people use total or partial prostheses [The National Center for Health Care Statistics http: //www.cdc.qov/nchs/) 1. In Chile, the use of dental prostheses appears in 50% of the plans of the "Dental Treatment Flowchart for 60-year-old adults" of the "Clinical Guide to Comprehensive Oral Health for 60-year-old Adults" of MINSAL (2010). Data from the "National Health Survey" carried out in 2003, indicate that more than 60% of the population over 65 are users of dental prostheses.
Como todo elemento externo, las prótesis deben tener un mantenimiento ligado principalmente a su limpieza, situación que no siempre se realiza de manera adecuada, lo que se ve incrementado en el caso de adultos mayores. Esta falencia favorece la formación de placa microbiana que en múltiples casos genera estados inflamatorios de la mucosa bucal, cuyos medios de cultivo son los restos de alimentos depositados en la prótesis. Lo anterior tiene como resultado la generación de un proceso inflamatorio crónico de la mucosa adyacente a la prótesis, conocido como estomatitis subprotésica. El diagnóstico de esta patología es fundamentalmente clínico y la sintomatología es variable, desde asintomática hasta cuadros con dolor y/o ardor de variada intensidad en la mucosa oral comprometida. La estomatitis subprotésica es una de las alteraciones que con más frecuencia se diagnostica dentro de las patologías bucales, y constituye un problema de salud oral que requiere alternativas de prevención y/o control más eficaces. Esta patología puede degenerar en una lesión hiperplásica si no se trata oportunamente. Generalmente se presenta en la mucosa de soporte, en pacientes portadores de prótesis removibles, las cuales comúnmente se encuentran en mal estado. La estomatitis subprotésica delimita y evita el uso óptimo de prótesis removibles, además que bajo esta condición clínica el usuario debe ser tratado según la guía con antimicóticos tópicos específicos, generando una carga económica relevante al servicio responsable de la atención. Estudios realizados revelan que la prevalencia de estomatitis subprotésica varía entre 25-65% [N. González, I. de Jesús et al., Prevalencia de la estomatitis subprótesis, AMC, Camagüey, v. 13, n. 1 , Feb. 2009, y Zissis A, Yannikakis S, Harrison A., Comparison of denture stomatitis prevalence in 2 population groups, Int J Prosthodont, 2006 Nov-Dec;19(6):621 -5], comprometiendo a sujetos cuyas edades fluctúan entre los 25 y 90 años. La patología tiene una prevalencia de un 40% en personas entre 50 a 65 años de edad, y presenta un predominio en el género femenino con una relación de 4:1 [La estomatitis subprotésica, Apuntes de Odontochile, www.odontochile.cll. En general se considera que las dos terceras partes de los portadores de prótesis removibles presentan estomatitis subprotésica en un grado variable. Like any external element, the prostheses must have a maintenance linked mainly to their cleaning, a situation that is not always carried out properly, which is increased in the case of older adults. This failure favors the formation of microbial plaque that in many cases generates inflammatory conditions of the oral mucosa, whose culture media are the remains of food deposited in the prosthesis. The above results in the generation of a chronic inflammatory process of the mucosa adjacent to the prosthesis, known as subprothetic stomatitis. The diagnosis of this pathology is fundamentally clinical and the symptomatology is variable, from asymptomatic to pictures with pain and / or burning of varied intensity in the compromised oral mucosa. Subprothetic stomatitis is one of the alterations that is most frequently diagnosed within oral pathologies, and constitutes an oral health problem that requires more effective prevention and / or control alternatives. This pathology can degenerate into a hyperplastic lesion if it is not treated in a timely manner. It usually occurs in the support mucosa, in patients with removable prostheses, which are commonly in poor condition. Subprothetic stomatitis delimits and avoids the optimal use of removable prostheses, in addition that under this clinical condition the user must be treated according to the guide with specific topical antifungals, generating a relevant economic burden to the service responsible for the care. Studies show that the prevalence of subprothetic stomatitis varies between 25-65% [N. González, I. de Jesús et al., Prevalence of sub-prosthetic stomatitis, AMC, Camagüey, v. 13, n. 1, Feb. 2009, and Zissis A, Yannikakis S, Harrison A., Comparison of denture stomatitis prevalence in 2 population groups, Int J Prosthodont, 2006 Nov-Dec; 19 (6): 621-5], engaging subjects whose ages fluctuate between 25 and 90 years. The pathology has a prevalence of 40% in people between 50 and 65 years of age, and has a predominance in the female gender with a ratio of 4: 1 [Subprothetic stomatitis, Notes of Odontochile, www.odontochile.cll. It is generally considered that two thirds of the carriers of removable prostheses have subprothetic stomatitis to a variable degree.
Aunque la estomatitis puede obedecer a factores locales tales como el desajuste de la prótesis, sistema inmune alterado ó consumo de tabaco; esta patología es generada principalmente por una infección microbiana. Se estima que un gran porcentaje es producto de una respuesta exagerada del organismo frente una infección de la mucosa por microorganismos que colonizan la superficie de la prótesis, en la mayoría de los casos hongos del género Candida. Estos patógenos son miembros comensales de la microbiota oral, y se encuentran presentes en alrededor del 40 por ciento de la población sin provocar problemas en la mayoría de estos. Sin embargo, su multiplicación descontrolada producto de un período de inmunosupresión o por la presencia de factores locales, permite la colonización de los tejidos del paciente. Esto genera alteraciones en la mucosa oral que se manifiestan con una serie de síntomas y signos que se conocen genéricamente como Candidiasis Oral. La Candidiasis Crónica Atrófica, es aquel tipo de candidiasis oral que se asocia directamente con el uso de prótesis removible, y se distingue de otros tipos de candidiasis porque se presenta en áreas que están cubiertas por los aparatos, como el paladar duro, apreciándose como un eritema y edema de la zona. La candidiasis crónica atrófica se puede manifestar como máculas hiperémicas bien definidas (Tipo I), como un eritema difuso de una parte o toda la zona cubierta por la prótesis (Tipo II), ó como una hiperplasia papilar (granular) que compromete el paladar duro o el reborde alveolar (Tipo III). Los microorganismos más relevantes responsables de esta infección son especies de levaduras del género Candida, tales como C. glabrata, C. tropicalis, C. kefyr, C. krusei y C. guilliermondii, sin embargo Candida albicans es la que con mayor frecuencia se aisla desde lesiones de la cavidad oral [Williams DW, Kuriyama T, Silva S, Malic S, Lewis MA (2002), Candida biofilms and oral candidosis: treatment and prevention, Postgrad Med J;78:455-459]. Se considera que C. albicans coloniza en primer lugar el dorso de la lengua y que, desde ahí, es capaz de invadir otros sitios de la cavidad oral como la mucosa, piezas dentarias ó materiales dentales que son colonizados en forma secundaria [Webb BC, Thomas CJ, Willcox MD, Harty DW, Knox KW (201 1 ), Candida-associated denture stomatitis, Aetiology and management: a review. Part 1 ; Factors influencing distribution of Candida species in the oral cavity, Aust Dent J 39(1 1 ):71 1 -9]. C. albicans es la especie que expresa una mayor cantidad de factores de virulencia asociados a la patogenicidad, entre los que se encuentran: capacidad para adherirse a las células del huésped (adhesión a la mucosa), secreción de proteinasas (destrucción de tejido), y cambios de morfología desde levaduras a pseudohifas e hifas. El principal mecanismo que permite que estos microorganismos puedan mantenerse en cavidad oral, es mediante la formación de biofilms sobre las superficies. El biofilm protege a las levaduras de la acción de remoción mecánica que producen la saliva, además funciona como barrera protectora frente a la penetración de factores de la respuesta inmune del huésped, así como de antimicrobianos administrados. Candida se adhiere inicialmente a las superficies en la forma de levadura, luego prolifera mediante un crecimiento de las levaduras y la generación de extensiones filamentosas pluricelulares en la forma de hifas. La existencia de la estomatitis subprotésica no solo afecta la calidad de vida de una gran parte de la población (el 60% del 20% de la población que usa prótesis dentales), especialmente en la tercera edad, afectando sus funciones normales tales como masticación, fonación y estética, sino que genera un gran costo económico directo. Este costo está relacionado con la necesidad de consultas dentales extras, y el someterse a controles y tratamientos que pueden considerar el recambio del dispositivo. Desde el punto de vista país, en los servicios de atención pública esta patología hace necesario una planificación especial, así como el empleo de recursos adicionales. Although stomatitis may be due to local factors such as the mismatch of the prosthesis, altered immune system or tobacco use; This pathology is mainly generated by a microbial infection. It is estimated that a large percentage is the product of an exaggerated response of the organism against an infection of the mucosa by microorganisms that colonize the surface of the prosthesis, in most cases fungi of the genus Candida. These pathogens are commensal members of the oral microbiota, and are present in about 40 percent of the population without causing problems in most of these. However, its uncontrolled multiplication due to a period of immunosuppression or Due to the presence of local factors, it allows colonization of the patient's tissues. This generates alterations in the oral mucosa that manifest with a series of symptoms and signs that are generically known as Oral Candidiasis. Chronic Atrophic Candidiasis, is that type of oral candidiasis that is directly associated with the use of removable prostheses, and is distinguished from other types of candidiasis because it occurs in areas that are covered by the devices, such as the hard palate, being seen as a Erythema and edema of the area. Chronic atrophic candidiasis can manifest as well-defined hyperemic macules (Type I), as a diffuse erythema of part or all of the area covered by the prosthesis (Type II), or as a papillary (granular) hyperplasia that compromises the hard palate or the alveolar flange (Type III). The most relevant microorganisms responsible for this infection are yeast species of the genus Candida, such as C. glabrata, C. tropicalis, C. kefyr, C. krusei and C. guilliermondii, however Candida albicans is the most frequently isolated from lesions of the oral cavity [Williams DW, Kuriyama T, Silva S, Malic S, Lewis MA (2002), Candida biofilms and oral candidosis: treatment and prevention, Postgrad Med J; 78: 455-459]. It is considered that C. albicans first colonizes the back of the tongue and that, from there, it is able to invade other sites of the oral cavity such as the mucosa, dental pieces or dental materials that are secondary colonized [Webb BC, Thomas CJ, Willcox MD, Harty DW, Knox KW (201 1), Candida-associated denture stomatitis, Aetiology and management: a review. Part 1; Factors influencing distribution of Candida species in the oral cavity, Aust Dent J 39 (1 1): 71 1-9]. C. albicans is the species that expresses a greater amount of virulence factors associated with pathogenicity, among which are: ability to adhere to host cells (adhesion to the mucosa), secretion of proteinases (tissue destruction), and morphology changes from yeast to pseudohyphae and hyphae. The main mechanism that allows these microorganisms to be kept in the oral cavity is through the formation of biofilms on the surfaces. Biofilm protects yeasts from the mechanical removal action that produces saliva, and also functions as a protective barrier against the penetration of host immune response factors, as well as administered antimicrobials. Candida initially adheres to the surfaces in the form of yeast, then proliferates through a growth of yeasts and the generation of multicellular filamentous extensions in the form of hyphae. The existence of subprothetic stomatitis not only affects the quality of life of a large part of the population (60% of the 20% of the population that uses dentures), especially in the elderly, affecting their normal functions such as chewing, phonation and aesthetics, but it generates a great direct economic cost. This cost is related to the need for extra dental consultations, and to undergo controls and treatments that may consider the replacement of the device. From the country point of view, this pathology requires special planning in the public attention services, as well as the use of additional resources.
Las terapias actuales, anteriormente mencionadas, para controlar la estomatitis, resultan efectivas siempre y cuando exista un compromiso de los pacientes con el tratamiento, y se logre modificar las condiciones que permiten la proliferación descontrolada de los microorganismos. Sin embargo, de acuerdo a la experiencia clínica, estas medidas de control en general no se cumplen, lo cual se traduce en una alta incidencia de esta patología en la población chilena, alcanzando un 22,3 %. El tratamiento, por lo general, es complejo lo que implica un gran costo económico para los pacientes, debido a la necesidad de asistir de manera frecuente al odontólogo, así como por el uso de fármacos y materiales que permitan restablecer la salud del tejido. Si se considera que los principales usuarios de este tipo de aparato son los grupos sociales de menores ingresos, surge la necesidad de buscar alternativas que permitan disminuir la incidencia de la candidiasis asociada al uso de prótesis removible. The current therapies, mentioned above, to control stomatitis, are effective as long as there is a commitment of the patients to the treatment, and the conditions that allow uncontrolled proliferation of microorganisms can be modified. However, according to clinical experience, these control measures in general are not met, which translates into a high incidence of this pathology in the Chilean population, reaching 22.3%. The treatment, in general, is complex, which implies a great economic cost for the patients, due to the need to attend the dentist frequently, as well as the use of drugs and materials that allow the restoration of tissue health. If the main users of this type of device are considered to be the lowest income social groups, there is a need to look for alternatives to reduce the incidence of candidiasis associated with the use of removable prostheses.
El tratamiento de un paciente con candidiasis oral generalmente considera varios aspectos. Como parte esencial del tratamiento, se instruye al paciente en una técnica de higiene apropiada que permita la remoción completa del biofilm, tanto desde la superficie de la mucosa así como desde la prótesis dental. Además de los procedimientos de remoción mecánica del biofilm, se recomienda el uso de enjuagues bucales que posean actividad frente a levaduras del género Candida como la clorhexidina y el triclosán. A los pacientes también se les enfatiza la importancia de dejar de fumar, debido a que el tabaco genera una mayor incidencia de candidiasis oral. Además, se busca detectar y corregir cualquier deficiencia en la dieta, tales como una inaproplada ingesta de carbohidrato. En la mayoría de los pacientes, estas medidas podrían ser suficientes para controlar la Infección, sin embargo existe un Importante porcentaje en los cuales a pesar de que se cumplan estas Intervenciones, no es posible controlar la enfermedad. Esto se debe a que existen otros factores involucrados, y que no pueden ser modificados. Entre estos se encuentran pacientes con VIH ó aquellos que han sido sometidos a trasplante de órganos, y que se encuentran bajo tratamiento con inmunosupresores. En estos casos particulares así como en aquellos en que la patología no se controla con las medidas iniciales, se recurre al tratamiento en base al uso de agentes antlfúngicos. Actualmente, se conocen una serle de antlfúngicos que han demostrado ser efectivos para el tratamiento de la candldiasls, tales como los pollenos (Nistatlna, Anfotericlna B), triazoles (Fluconazol, Itraconazol, Vorlconazol y Posaconazol), Equlnocandinas (Caspofunglna, Micafunglna, Anidulafunglna), y Flucltosina. Estos fármacos pueden ser administrados tópicamente o de manera slstémica. Sin embargo, el uso de antlfúngicos también puede producir una serle de reacciones adversas, tales como dolores de cabeza, nauseas, vómitos y malestar gastrointestinal en general. Debido a su mecanismo de eliminación, algunos fármacos slstémicos pueden ser hepatotóxlcos, ó generar neutropenla. Los anifúnglcos sistémlcos en general también ¡nteractúan con otros medicamentos, por lo que se debe realizar una completa anamnesis antes de prescribirlos. Es por esta razón, que los odontólogos tratan de evitar el uso de antlfúngicos slstémicos, y solo se prescriben en situaciones claramente justificadas. En el caso de candldiasls menos agresivas, los antlfúngicos tópicos son la primera línea terapéutica. Estas sustancias, generalmente tienen una favorable respuesta al ser utilizadas en contacto directo con la lesión. Sin embargo, la administración tópica suelen ser poco efectiva en comparación con el uso slstémico, debido a la necesidad de la aplicación frecuente del fármaco en la superficie afectada, lo que no siempre es realizado por los pacientes. Además, los fármacos tópicos se caracterizan por presentar sabores muy desagradables, generar Incomodidad durante su uso y mantenerse por poco tiempo en contacto con la mucosa oral. Por otra parte, también se pueden producir varias reacciones adversas por el contacto del fármaco con la lesión, en este caso las más Importantes corresponden a la Irritación de la mucosa o la piel, alteraciones en el gusto y ardor de la zona. En un estudio reciente publicado por AL-Dwairi et al., se concluye que la exposición del acrílico de prótesis (PMMA) a los antifúngicos tópicos, puede también afectar la rugosidad, mojabilidad y energía libre superficial del material protésico. Los resultados de este estudio muestran que los cambios producidos por el antifúngico en el acrílico, paradójicamente incrementan la adhesión de C. albicans en el material. The treatment of a patient with oral candidiasis generally considers several aspects. As an essential part of the treatment, the patient is instructed in an appropriate hygiene technique that allows the complete removal of the biofilm, both from the surface of the mucosa and from the dental prosthesis. In addition to the mechanical removal procedures of biofilm, the use of mouthwashes that have activity against yeasts of the genus Candida such as chlorhexidine and triclosan is recommended. Patients are also emphasized the importance of quitting smoking, because tobacco generates a higher incidence of oral candidiasis In addition, it seeks to detect and correct any deficiency in the diet, such as an inappropriate intake of carbohydrate. In most patients, these measures may be sufficient to control the infection, however there is a significant percentage in which despite these interventions are fulfilled, it is not possible to control the disease. This is because there are other factors involved, and they cannot be modified. Among these are patients with HIV or those who have undergone organ transplantation, and who are under treatment with immunosuppressants. In these particular cases as well as in those in which the pathology is not controlled with the initial measures, treatment is used based on the use of antlfungal agents. Currently, a series of antlfungals are known that have proven effective for the treatment of candldiasls, such as pollens (Nistatlna, Amphotericin B), triazoles (Fluconazole, Itraconazole, Vorlconazole and Posaconazole), Equlnocandins (Caspofunglna, Micafunglna, Ancafunglna) , and Flucltosine. These drugs can be administered topically or in a systemic way. However, the use of antlfungals can also cause a series of adverse reactions, such as headaches, nausea, vomiting and gastrointestinal discomfort in general. Due to its elimination mechanism, some stremic drugs can be hepatotoxic, or generate neutropenla. Systemic anifúnglcos in general also interact with other medications, so a complete history should be performed before prescribing them. It is for this reason that dentists try to avoid the use of sttemic antlfungals, and are only prescribed in clearly justified situations. In the case of less aggressive candldiasls, topical antlfungals are the first therapeutic line. These substances generally have a favorable response when used in direct contact with the lesion. However, topical administration is usually ineffective compared to the use of the disease, due to the need for frequent application of the drug on the affected surface, which is not always done by patients. In addition, topical drugs are characterized by very unpleasant flavors, generate discomfort during use and keep for a short time in contact with the oral mucosa. On the other hand, several adverse reactions can also occur due to the contact of the drug with the lesion, in this case the most important ones correspond to the irritation of the mucosa or the skin, alterations in the taste and burning of the area. In a recent study published by AL-Dwairi et al., It is concluded that exposure of prosthetic acrylic (PMMA) to topical antifungals can also affect the roughness, wettability and surface free energy of the prosthetic material. The results of this study show that the changes produced by the antifungal in acrylic, paradoxically increase the adhesion of C. albicans in the material.
En resumen, el alto impacto de esta patología y el crecimiento que se pronostica debido al constante aumento en la población más vulnerable como es la tercera edad, hace que se genera una demanda por soluciones innovadoras que ayuden a aminorarla. Dentro de este contexto, surge la oportunidad de desarrollar un nuevo tipo de prótesis que contengan agentes antimicrobianos que ayuden a minimizar la prevalencia de esta enfermedad. Es así que se propone el desarrollo de nuevas resinas con partículas de cobre de tal manera de generar materiales que sean capaces de liberar en forma controlada el agente activo (iones metálicos) y así evitar el desarrollo de esta patología. In summary, the high impact of this pathology and the growth that is forecasted due to the constant increase in the most vulnerable population such as the elderly, leads to a demand for innovative solutions that help to reduce it. Within this context, the opportunity arises to develop a new type of prosthesis that contains antimicrobial agents that help minimize the prevalence of this disease. Thus, it is proposed to develop new resins with copper particles in such a way to generate materials that are capable of releasing the active agent (metal ions) in a controlled manner and thus prevent the development of this pathology.
Es así como, una aproximación al desarrollo de resinas antimicrobianas a base de cobre presenta un desafío científico y tecnológico desde varios puntos de vistas. El fundamento del desafío se basa en la necesidad de desarrollar partículas de cobre nanométricas o nanoestructuradas que sean estables en la matriz polimérica usada en las prótesis dentales. Para esto, es necesario encontrar la mejor nanopartícula de cobre a incorporar además de la mejor metodología para preparar el composito polimérico. Además, este composito debe presentar una liberación controlada de los iones cobre a una tasa que sea menor a la mínima requerida para evitar la toxicidad y cercana a las concentraciones necesarias para que tenga un efecto biocida. Todo lo anterior, sin alterar el proceso de polimerización y/o curado de la resina, o el proceso actual de preparación comercial de las prótesis. Desde el punto de vista tecnológico, las nuevas prótesis deben mantener las propiedades estructurales de la resina original, sin alteración sustancial en su coloración o estética. Lo anterior plantea nuevos desafíos relacionados al tipo de partícula de cobre, concentración, y su distribución en la matriz polimérica. En la presente Invención se desarrolla un material antimicrobiano para prótesis, utilizando elementos y técnicas que ofrece actualmente la nanotecnología. Particularmente, el uso de cobre metálico con tamaño de partícula nanométrico, a diferencia de la utilización de las sales de iones de cobre más estudiadas tradicionalmente. El nuevo material antifúngico corresponde a un nanocompósito, es decir aquel material compuesto que combina materiales de distinta naturaleza en donde uno de ellos posee dimensiones nanométricas. La preparación de este nanocompósito utilizando el actual acrílico de prótesis como matriz polimérica y las partículas de cobre nanométricas (CuNPs) como el componente antimicrobiano, constituye el aspecto central de la invención. Thus, an approach to the development of copper-based antimicrobial resins presents a scientific and technological challenge from several points of view. The rationale for the challenge is based on the need to develop nanometric or nanostructured copper particles that are stable in the polymer matrix used in dental prostheses. For this, it is necessary to find the best copper nanoparticle to incorporate in addition to the best methodology to prepare the polymeric composite. In addition, this compound must have a controlled release of copper ions at a rate that is less than the minimum required to avoid toxicity and close to the concentrations necessary for it to have a biocidal effect. All of the above, without altering the polymerization and / or curing process of the resin, or the current commercial preparation process of the prostheses. From the technological point of view, the new prostheses must maintain the structural properties of the original resin, without substantial alteration in their color or aesthetics. This poses new challenges related to the type of copper particle, concentration, and its distribution in the polymer matrix. In the present invention an antimicrobial material for prostheses is developed, using elements and techniques currently offered by nanotechnology. Particularly, the use of metallic copper with nanometric particle size, unlike the use of copper salts more traditionally studied. The new antifungal material corresponds to a nanocomposite, that is to say that composite material that combines materials of different nature where one of them has nanometric dimensions. The preparation of this nanocomposite using the current prosthetic acrylic as a polymeric matrix and nanometric copper particles (CuNPs) as the antimicrobial component, constitutes the central aspect of the invention.
La preparación de este material nanocompósito considera encontrar las condiciones más adecuadas para la incorporación de las CuNPs en la matriz, pero todo aquello conjugado con las propiedades antimicrobianas, estéticas (color), mecánicas y de citocompatibilidad del material resultante. El método más tradicional para la preparación de nanocompositos poliméricos consiste en la mezcla física del polímero fundido ó disuelto en algún solvente con las nananopartículas (método ex situ). La fabricación de una prótesis dental es un proceso de polimerización que ocurre sobre un material descartable, que posee el registro dental del paciente, dado por la posición de piezas dentales artificiales. De este modo, el uso del método ex situ, requeriría disolver las prótesis dentales ya fabricadas, razón por lo que no es factible para esta aplicación.  The preparation of this nanocomposite material considers finding the most suitable conditions for the incorporation of the CuNPs in the matrix, but all that combined with the antimicrobial, aesthetic (color), mechanical and cytocompatibility properties of the resulting material. The most traditional method for the preparation of polymeric nanocomposites consists in the physical mixing of the molten or dissolved polymer in some solvent with the nanoparticles (ex situ method). The manufacture of a dental prosthesis is a polymerization process that occurs on a disposable material, which has the patient's dental record, given by the position of artificial teeth. Thus, the use of the ex situ method would require dissolving the already manufactured dental prostheses, which is why it is not feasible for this application.
En un trabajo previo realizado por los inventores (Correa, S., Preparación de Resinas Acrílicas cargadas con nanopartículas de cobre y sus propiedades antimicrobianas frente a Candida Albicans, Instituto de Ciencias Odontológicas. 2012, Universidad de Chile: Santiago de Chile), se estudió la incorporación de CuNP en acrílico de prótesis dentales. En este estudio se utilizó el monómero metil metacrilato y un solvente orgánico como agentes reductores para permitir la formación in situ de las nanopartículas de cobre durante el proceso de polimerización del acrílico mediante autocurado. Se observó que el material acrílico nanocompósito cargado con CuNPs, posee una marcada actividad antimicrobiana frente a la especie Candida albicans, permitiendo inhibir el crecimiento de Candida albicans en el material de prótesis sobre un 80% con respecto al control. Este efecto resultó ser proporcional al contenido de CuNPs en el compósito. El efecto antimicrobiano del acrílico (CuNP/PMMA) fue sostenido en el tiempo, lo cual indica que las CuNPs y/o iones de cobre, se liberan gradualmente al medio [31 ]. El método desarrollado, así como el nuevo material, aparecen como una promisoria alternativa para el control de infecciones subprótesicas causadas por Candida albicans. Adicionalmente, la presencia de cobre en el material de prótesis, también podría tener un control sobre el desarrollo de patógenos periodontales. Estudios previos de nuestro grupo de laboratorio, han desarrollado geles de biopolímero cargados con nanopartículas de cobre, que son capaces de inhibir el crecimiento de Aggregatibacter actinomycetemcomitans (González, J.P., Síntesis de materiales bactericidas basados en nanopartículas metálicas y biopolímeros para terapia periodontal odontológica. Instituto de Ciencias Odontológicas. 2013, Universidad de Chile: Santiago de Chile). Esto nos indicaría que la presencia de nanopartículas de cobre en el acrílico, y por consiguiente su interacción con la cavidad oral, podría reducir el crecimiento de patógenos periodontales. In a previous work carried out by the inventors (Correa, S., Preparation of Acrylic Resins loaded with copper nanoparticles and their antimicrobial properties against Candida Albicans, Institute of Dental Sciences. 2012, University of Chile: Santiago de Chile), we studied the incorporation of CuNP in acrylic dentures. In this study, methyl methacrylate monomer and an organic solvent were used as reducing agents to allow the formation of copper nanoparticles in situ during the polymerization process of acrylic by self-curing. It was observed that the nanocomposite acrylic material loaded with CuNPs, has a marked antimicrobial activity against the Candida albicans species, allowing to inhibit the growth of Candida albicans in the prosthesis material by 80% with respect to the control. This effect proved to be proportional to the content of CuNPs in the compound The antimicrobial effect of acrylic (CuNP / PMMA) was sustained over time, which indicates that CuNPs and / or copper ions are gradually released to the medium [31]. The method developed, as well as the new material, appear as an promising alternative for the control of subprottic infections caused by Candida albicans. Additionally, the presence of copper in the prosthetic material could also have control over the development of periodontal pathogens. Previous studies of our laboratory group have developed biopolymer gels loaded with copper nanoparticles, which are capable of inhibiting the growth of Aggregatibacter actinomycetemcomitans (González, JP, Synthesis of bactericidal materials based on metal nanoparticles and biopolymers for dental periodontal therapy. Institute of Dental Sciences 2013, University of Chile: Santiago de Chile). This would indicate that the presence of copper nanoparticles in the acrylic, and therefore their interaction with the oral cavity, could reduce the growth of periodontal pathogens.
La aproximación al desarrollo de esta resina antimicrobiana a base de cobre presenta un desafío científico y tecnológico desde varios puntos de vista. El fundamento del desafío se basa en la necesidad de desarrollar partículas de cobre nanométricas o nanoestructuradas que sean estables en la matriz polimérica usada para las prótesis dentales. Para esto, es necesario encontrar la mejor nanopartícula de cobre a incorporar (tamaño, naturaleza, forma), además de la mejor metodología para preparar el compósito polimérico. Además, este compósito debe presentar liberación controlada de los iones cobre a una tasa que sea menor a la mínima requerida para evitar la toxicidad y cercana a las concentraciones necesarias para que tenga un efecto biocida. Todo lo anterior, sin alterar la etapa de polimerización de la resina en el proceso actual de preparación comercial de las prótesis. En el estudio de tesis anterior, se trabajó con acrílicos de autopolimerización, por lo que en el presente proyecto tesis se propone la optimización del proceso de preparación del nanocompósito en condiciones de termopolimerización, el cual es el proceso utilizado comercialmente para la fabricación de prótesis dentales. Se considerará además comparar el proceso in situ previamente desarrollado con el método proceso tradicional ex situ. En este último procedimiento, la CuNP es sintetizada previamente mediante otra técnica, y luego incorporada a la matriz polimérica. Este nuevo material tendría propiedades antlmlcroblanas frente a Candida albicans, Inhibiendo su crecimiento, y de este modo, previniendo o tratando la estomatitis subprótesica. También se esperaría que el nuevo material de prótesis, presente actividad antimlcrobiana frente a patógenos perlodontales. Esto último podría tener consecuencias en controlar las Infecciones perlodontales en pacientes parcialmente desdentados (portadores de prótesis), y así estimular la salud perlodontal de los dientes remanentes, mejorando su pronóstico en boca. Por otro lado, las nuevas prótesis deben mantener las propiedades estructurales de la resina original, sin alteración sustancial en su color desde el punto de vista estético - odontológico. Lo anterior plantea la necesidad de optimizar del proceso de preparación del material nanocompósito de prótesis en función de las diferentes propiedades (antlmicroblanas, mecánicas, color), relacionados al tipo de partícula de cobre, concentración, método de Incorporación y su distribución en la matriz pollmérica entre otras variables. The approach to the development of this copper-based antimicrobial resin presents a scientific and technological challenge from several points of view. The rationale for the challenge is based on the need to develop nanometric or nanostructured copper particles that are stable in the polymer matrix used for dental prostheses. For this, it is necessary to find the best copper nanoparticle to incorporate (size, nature, shape), in addition to the best methodology to prepare the polymeric compound. In addition, this compound must have controlled release of copper ions at a rate that is less than the minimum required to avoid toxicity and close to the concentrations necessary for it to have a biocidal effect. All of the above, without altering the stage of polymerization of the resin in the current commercial preparation process of the prostheses. In the previous thesis study, self-curing acrylics were worked on, so in this thesis project the optimization of the nanocomposite preparation process under thermopolymerization conditions is proposed, which is the process used commercially for the manufacture of dental prostheses . It will also be considered to compare the previously developed in situ process with the traditional ex situ process method. In this last procedure, the CuNP is previously synthesized by another technique, and then incorporated into the polymer matrix. This new material would have antlmlcroblanas properties against Candida albicans, inhibiting its growth, and thus, preventing or treating subprottic stomatitis. The new prosthetic material would also be expected to present antimlcrobial activity against perlodontal pathogens. The latter could have consequences in controlling perlodontal infections in partially edentulous patients (prosthesis carriers), and thus stimulate the perlodontal health of the remaining teeth, improving their prognosis in the mouth. On the other hand, the new prostheses must maintain the structural properties of the original resin, without substantial alteration in its color from the aesthetic - dental point of view. The above raises the need to optimize the process of preparation of the nanocomposite prosthesis material based on the different properties (antlmicroblanes, mechanics, color), related to the type of copper particle, concentration, method of Incorporation and its distribution in the polymer matrix Among other variables.
La presente Invención se enfoca en la preparación de un material nanocompósito a base de nanopartículas de cobre y pollmetilmetacrllato de termocurado; con propiedades antlmicroblanas frente Candida albicans; optimizando sus propiedades mecánicas, de cltocompatibllldad y estéticas, el cual utiliza un método in situ de formación del nanocompósito, Incorporando las nanopartículas durante el proceso de polimerización. En este caso las partículas previamente sintetizadas, son incorporadas dispersándolas en alguno de los componentes de la reacción (monómeros, solvente), para luego permitir que ocurra la polimerización. La invención no solo se propone la preparación in situ del nanocompósito, sino que también las CuNPS se sintetiza durante el proceso de polimerización. Dicho proceso se plantea basado en las propiedades reductoras que posee el monómero metllmetacrllato, y que podrían ser potenciadas por la adición de pequeñas fracciones de algún solvente orgánico, como etanol. De este modo las CuNPs pueden ser formadas por la acción reductora del monómero sobre Iones de cobre Incorporados a partir de una sal del metal. Este tipo de procesos de formación in situ de la nanopartícula, permiten una incorporación más eficiente y una dispersión más homogénea de la partícula en la matriz del nanocompósito. Estos aspectos son factores conocidos que favorecen las propiedades bloactivas, mecánicas y ópticas (color) del compósito obtenido. De manera adicional se considera la preparación del nanocompósito, utilizando CuNPs previamente sintetizadas por otros métodos. En este caso se usarán CuNPs disponibles comercialmente, así como CuNPs soportadas sobre partículas de un material cerámico. Este último enfoque también constituye una importante contribución desde el punto de vista científico. The present invention focuses on the preparation of a nanocomposite material based on copper nanoparticles and thermoset polyethylene methacrylate; with anti-microbial properties against Candida albicans; optimizing its mechanical, cltocompatibility and aesthetic properties, which uses an in situ method of nanocomposite formation, incorporating the nanoparticles during the polymerization process. In this case the previously synthesized particles are incorporated by dispersing them in some of the reaction components (monomers, solvent), to then allow polymerization to occur. The invention not only proposes the in situ preparation of the nanocomposite, but also CuNPS is synthesized during the polymerization process. This process is based on the reducing properties that the metllmetacrllato monomer possesses, and that could be enhanced by the addition of small fractions of some organic solvent, such as ethanol. In this way the CuNPs can be formed by the reducing action of the monomer on copper ions incorporated from a metal salt. This type of nanoparticle formation process in situ, allows a more efficient incorporation and a more homogeneous dispersion of the particle in the nanocomposite matrix. These aspects are known factors that favor the blocking properties, mechanical and optical (color) of the composite obtained. Additionally, the preparation of the nanocomposite is considered, using CuNPs previously synthesized by other methods. In this case, commercially available CuNPs will be used, as well as CuNPs supported on particles of a ceramic material. This last approach also constitutes an important contribution from the scientific point of view.
El cobre soportado sobre matrices cerámicas tienen en promedio una menor densidad y un menor impacto sobre la coloración de compósitos poliméricos. Copper supported on ceramic matrices on average have a lower density and a lower impact on the coloration of polymeric composites.
Además, como parte del desarrollo de la presente invención, se ha desarrollado un método que permite la síntesis de CuNPs sobre materiales cerámicos nanoestructurados como zeolitas ó sílice. Las zeolitas son aluminosilicatos cristalinos que presentan una nanoestructura constituida por poros, canales y cavidades con dimensiones sub-nanométricas. De este modo, se puede obtener un material cobre-zeolita, en donde las nanopartículas del metal se encuentran soportadas en el interior de las cavidades del material cerámico. El procedimiento de síntesis de las CuNPs soportadas en partículas cerámicas, utiliza agentes reductores biocompatibles, lo que hace de estos materiales particularmente más apropiados para aplicaciones biomédicas. In addition, as part of the development of the present invention, a method has been developed that allows the synthesis of CuNPs on nanostructured ceramic materials such as zeolites or silica. Zeolites are crystalline aluminosilicates that have a nanostructure consisting of pores, channels and cavities with sub-nanometric dimensions. In this way, a copper-zeolite material can be obtained, where the metal nanoparticles are supported inside the cavities of the ceramic material. The synthesis procedure of CuNPs supported on ceramic particles uses biocompatible reducing agents, which makes these materials particularly suitable for biomedical applications.
Debido a que en el estado del arte no se reportan estudios de preparación de acrílico dental con CuNPs, son de interés todas las técnicas y estrategias de síntesis para la preparación de acrílicos dentales con propiedades antimicrobianas. La aplicación de estos procedimientos se extiende a cualquier tipo de resinas acrílicas dentales, tales como las usadas en compositos de restauración, adhesivos de restauración, adhesivos ortodóncicos, sellantes, ó vidrios ionómeros; aplicaciones en las que el control antimicrobiano es un aspecto de actual interés. Because studies of dental acrylic preparation with CuNPs are not reported in the state of the art, all techniques and synthesis strategies for the preparation of dental acrylics with antimicrobial properties are of interest. The application of these procedures extends to any type of dental acrylic resins, such as those used in restorative composites, restorative adhesives, orthodontic adhesives, sealants, or ionomer glasses; applications in which antimicrobial control is an aspect of current interest.
La prótesis dental fabricada con el material nanocompósito presenta un marcado efecto antimicrobiano frente a C.albicans y Streptococcus mutans debido a las reconocidas propiedades antimicrobianas del cobre, particularmente por ser un efectivo antifúngico. De acuerdo a los principios de la nanotecnología, partículas de cobre con tamaño nanométrico deberían presentar una mayor actividad, lo cual se traduce en que bajos contenidos del metal pueden producir un importante efecto antimicrobiano. Las propiedades antifúngicas del nanocompósito están dadas por el efecto fungicida ó antifouling (antiadherente) que presenta el cobre. Estos efectos se producen por una controlada liberación de las partículas de cobre desde la matriz polimérica, al exponer el nanocompósito con el medio acuoso. Comúnmente las matrices poliméricas también sufren erosión en contacto con el medio fisiológico, lo cual también facilitaría la liberación de cobre desde la superficie del nanocompósito. Adicionalmente se ha demostrado que las moléculas de agua pueden penetrar entre las cadenas poliméricas, oxidando las nanopartículas, produciendo su difusión y posterior liberación desde la matriz polimérica en forma de iones. El uso de diferentes técnicas avanzadas de caracterización tales como XPS, complementado con estudios de liberación de cobre en medio acuoso y ensayos microbiológicos; hacen que se pueda llegar a comprender de manera bastante cercana, el modo de acción antifúngico del nuevo material. The dental prosthesis manufactured with the nanocomposite material has a marked antimicrobial effect against C. albicans and Streptococcus mutans due to the recognized antimicrobial properties of copper, particularly as an antifungal effective. According to nanotechnology principles, copper particles with nanometric size They should have a higher activity, which means that low metal contents can produce an important antimicrobial effect. The antifungal properties of the nanocomposite are given by the fungicidal or antifouling effect of copper. These effects are produced by a controlled release of the copper particles from the polymer matrix, by exposing the nanocomposite with the aqueous medium. Commonly polymeric matrices also suffer erosion in contact with the physiological environment, which would also facilitate the release of copper from the surface of the nanocomposite. Additionally it has been shown that water molecules can penetrate between the polymer chains, oxidizing the nanoparticles, producing their diffusion and subsequent release from the polymer matrix in the form of ions. The use of different advanced characterization techniques such as XPS, complemented with studies of copper release in aqueous medium and microbiological assays; they make it possible to understand, quite closely, the antifungal mode of action of the new material.
Las actuales soluciones al problema de la estomatitis subprotésica se centran principalmente en la aplicación de antimicóticos tópicos sobre la mucosa afectada. Aún cuando el tratamiento con antimicóticos puede llegar a remediar la infección, los procedimientos de aplicación tópica no siempre son seguidos adecuadamente por los pacientes, especialmente por aquellos pertenecientes a la tercera edad. Los antimicóticos tópicos además se caracterizan particularmente por poseer desagradables sabores, generar incomodidad durante su uso y de mantenerse por poco tiempo en contacto con la mucosa oral. Debido a las desventajas que presentan los antimicóticos tópicos, así como por las limitaciones que tienen los pacientes para seguir los protocolos de aplicación del antimicótico; se requieren nuevas alternativas de solución para este problema de salud oral. Estrategias orientadas a prevenir el desarrollo de la enfermedad resultan siempre más recomendables para la salud de la población. En este contexto el desarrollo de prótesis dentales con propiedades antimicrobianas parece ser una alternativa atractiva para el control de la infección oral. El dispositivo dental fabricado con un material especialmente formulado para tener un efecto antimicrobiano frente a C. albicans, debería reducir significativamente la aparición de estomatitis producida por aquel patógeno. Por lo cual, el nuevo material de prótesis se desarrolla con elementos que actualmente entrega la nanotecnología. Esta disciplina basada en el control de la materia a una escala nanométrica (10~9 m) para generar productos con mejoradas o nuevas propiedades, se encuentra globalmente afectando diversos ámbitos de impacto industrial y social. En el ámbito odontológico, la influencia de los nanomateriales se puede encontrar por ejemplo en las actuales resinas nanocompositas de restauración dental, que presentan mayor durabilidad y mejoradas propiedades estéticas. The current solutions to the problem of subprothetic stomatitis mainly focus on the application of topical antifungals on the affected mucosa. Even when treatment with antifungals can remedy the infection, topical application procedures are not always followed adequately by patients, especially those belonging to the elderly. Topical antifungals are also particularly characterized by having unpleasant flavors, generating discomfort during use and keeping for a short time in contact with the oral mucosa. Due to the disadvantages of topical antifungals, as well as the limitations that patients have to follow the antifungal application protocols; New alternative solutions are required for this oral health problem. Strategies aimed at preventing the development of the disease are always more recommended for the health of the population. In this context the development of dental prostheses with antimicrobial properties seems to be an attractive alternative for the control of oral infection. The dental device made of a material specially formulated to have an antimicrobial effect against C. albicans, should significantly reduce the appearance of stomatitis caused by that pathogen. Therefore, the new prosthetic material is developed with elements currently delivered Nanotechnology This discipline based on the control of matter on a nanometric scale (10 ~ 9 m) to generate products with improved or new properties, is globally affecting various areas of industrial and social impact. In the dental field, the influence of nanomaterials can be found for example in the current dental restoration nanocomposites resins, which have greater durability and improved aesthetic properties.
En los últimos años se ha encontrado que nanopartículas de cobre son más efectivas como agentes antimicrobianos que micropartículas, lo que abre oportunidades en nanotecnología en el ámbito de materiales antimicrobianos. Lo anterior justifica el uso de estas partículas como agentes a incorporar en matrices plásticas, como se ha visto en otros sistemas como por ejemplo en polímero/plata. Aunque las propiedades antimicrobianas del cobre nanométrico son conocidas en otros ámbitos de aplicación, no se conoce su uso en productos dentales, lo cual constituye un componente de investigación e innovador de la presente propuesta. In recent years, copper nanoparticles have been found to be more effective as antimicrobial agents than microparticles, which opens up opportunities in nanotechnology in the field of antimicrobial materials. This justifies the use of these particles as agents to be incorporated in plastic matrices, as seen in other systems such as polymer / silver. Although the antimicrobial properties of nanometric copper are known in other fields of application, their use in dental products is not known, which constitutes a research and innovative component of this proposal.
El material antimicrobiano consiste en un nanocomposito, esto es un material compuesto que combina materiales de distinta naturaleza (polímero y metal) y en donde alguno de ellos posee dimensiones nanométricas. El nanocomposito está constituido por una matriz de polimetilmetacrilato (PMMA), la que llevará dispersa diversas nanopartículas de cobre (CuNPs). La selección de la matriz se basa en su amplio uso en aplicaciones de prótesis, de manera de facilitar su incorporación en el mercado. The antimicrobial material consists of a nanocomposite, this is a composite material that combines materials of different nature (polymer and metal) and where some of them have nanometric dimensions. The nanocomposite is constituted by a matrix of polymethylmethacrylate (PMMA), which will carry various copper nanoparticles (CuNPs). The selection of the matrix is based on its wide use in prosthetic applications, in order to facilitate its incorporation into the market.
La presente invención se focaliza en desarrollar la tecnología más adecuada para fabricar el material nanocomposito, conjugando las variables de preparación con sus propiedades antimicrobianas frente al C. albicans; así como con su características mecánicas y estéticas. El proceso de formación del nanocomposito considera la síntesis in situ de las CuNPs durante la polimerización del PMMA, aunque alternativamente se considerará también la incorporación ex situ de las partículas metálicas, variando el porcentaje de carga en la matriz. El objetivo es encontrar la mejor partícula, su contenido en la matriz polimérica y el método más apropiado para su incorporación, teniendo en cuenta el comportamiento antimicrobiano, estético y mecánico del material nanocompósito resultante, The present invention focuses on developing the most suitable technology for manufacturing the nanocomposite material, combining the preparation variables with their antimicrobial properties against C. albicans; as well as with its mechanical and aesthetic characteristics. The nanocomposite formation process considers the in situ synthesis of the CuNPs during the polymerization of the PMMA, although alternatively the ex situ incorporation of the metal particles will also be considered, varying the percentage of charge in the matrix. The objective is to find the best particle, its content in the polymer matrix and the most appropriate method for its incorporation, taking into account the antimicrobial, aesthetic and mechanics of the resulting nanocomposite material,
En la Figura 1 se esquematiza el proceso de preparación del nanocompósito. En el procedimiento in situ se utiliza como precursor de las CuNPs una sal de cobre, mientras que los procesos ex situ se usan CuNPs puras en polvo o un material cerámico como zeolita ó sílice modificado con cobre En general, en el método in situ el precursor de la CuNP es incorporado en el mónomero, para luego ser mezclado con el polímero de acuerdo al procedimiento tradicional de preparación de acrílico de prótesis y producir la polimerización mediante auto o termo curado. Estas diferentes metodologías permiten optimizar el proceso de obtención de la resina antimicrobiana de manera de encontrar la mejor formulación, y son el fundamento de la innovación que muestra la presente invención dado que se contempla diferentes aspectos como por ejemplo la coloración. En particular, el cobre soportado en una matriz inorgánica tiene en promedio una baja densidad y menor impacto en la coloración de la matriz. The preparation process of the nanocomposite is schematized in Figure 1. In the in situ process a copper salt is used as a precursor to the CuNPs, while the ex situ processes use pure powder CuNPs or a ceramic material such as zeolite or copper modified silica In general, in the in situ method the precursor CuNP is incorporated into the monomer, and then mixed with the polymer according to the traditional procedure of preparing acrylic prostheses and producing polymerization by self or thermosetting. These different methodologies make it possible to optimize the process of obtaining the antimicrobial resin in order to find the best formulation, and are the foundation of the innovation shown by the present invention since different aspects are contemplated, such as coloring. In particular, copper supported in an inorganic matrix has a low density on average and less impact on the color of the matrix.
Figure imgf000032_0001
Figure imgf000032_0001
Figura 1 . Esquema del procedimiento de síntesis del material nanocompósito CuNP/PMMA. Se considera que al adicionar nanopartículas de cobre a la resina que se utiliza actualmente en prótesis, se genera un nuevo material antimicrobiano con propiedades estéticas y mecánicas similares a las resinas usadas actualmente. Esto dado que el cobre es un agente antimicrobiano efectivo, siendo sus nanopartículas más efectivas que sus micropartículas. Además, al ser las partículas de tamaño nanométrico, estas no afectan considerablemente el desempeño de la matriz original. Todo esto justifica nuestra aproximación basado en nanotecnología. Figure 1 . Scheme of the synthesis procedure of the CuNP / PMMA nanocomposite material. It is considered that by adding copper nanoparticles to the resin that is currently used in prostheses, a new antimicrobial material with aesthetic and mechanical properties similar to the resins currently used is generated. This is because copper is an effective antimicrobial agent, its nanoparticles being more effective than its microparticles. In addition, being the particles of nanometric size, these do not significantly affect the performance of the original matrix. All this justifies our approach based on nanotechnology.
Con respecto al mecanismo de acción antimicrobiana del nuevo material nanocomposito, se observa que éste ejerce una acción antimicrobiana fundamentalmente mediante la liberación de iones de cobre al medio (Figura 2). Los iones se liberan de manera sostenida desde el seno de la matriz del polímero, las que ejercen una acción fungicida sobre los microorganismos existentes que entran en contacto con la superficie del material o se localizan en la vecindad de la interfase . Este mecanismo reducen la viabilidad y adhesión del patógeno en la superficie del material protésico, así como en la mucosa que se encuentra en contacto con el dispositivo dental. Estas propiedades del nuevo material de prótesis, crean las condiciones antimicrobianas para prevenir o tratar la infección subprotésica. With respect to the mechanism of antimicrobial action of the new nanocomposite material, it is observed that it exerts an antimicrobial action mainly through the release of copper ions to the medium (Figure 2). The ions are released in a sustained manner from within the polymer matrix, which exert a fungicidal action on existing microorganisms that come into contact with the surface of the material or are located in the vicinity of the interface. This mechanism reduces the viability and adhesion of the pathogen on the surface of the prosthetic material, as well as in the mucosa that is in contact with the dental device. These properties of the new prosthetic material create antimicrobial conditions to prevent or treat subprothetic infection.
Figure imgf000033_0001
Figure imgf000033_0001
Figura 2. Posibles mecanismos de acción antifúngica del nanocomposito CuNP/PMMA Figure 2. Possible mechanisms of antifungal action of the CuNP / PMMA nanocomposite
Con respecto a las regulaciones existentes para el uso de cobre en seres humanos, la Food and Drug Administration (FDA) considera niveles máximos de cobre en agua embotellada para consumo de 1 mg/mL (FDA 2001 a). Por otro lado el Institute of Occupational Medicine (IOM) informa una dieta recomendada permitida (RDA) de 0,9 mg/día, así como una ingesta tolerable máxima de 10 mg/día. En la presente Invención, los nanocompositos poseen un contenido de cobre de entre aproximadamente 30-150 μg/g. El material acrílico de una base de prótesis tiene una masa de aproximadamente 10 g, por lo que una prótesis fabricada con el nanocompósito posee contenidos máximos de cobre entre 0,3-1 ,5 mg. Esto sugiere que la cantidad de cobre liberado en la cavidad oral se debe encontrar bajo los niveles recomendados en algunas de las regulaciones. Además, se realizaron estudios de citoxicidad de cada uno de los materiales formulados, de manera de optimizar la actividad antmicrobiana del nanocompósito en función de los niveles de cobre biotolerables e indicados por las regulaciones existentes. With respect to existing regulations for the use of copper in humans, the Food and Drug Administration (FDA) considers maximum levels of copper in bottled water for consumption of 1 mg / mL (FDA 2001 a). On the other hand, the Institute of Occupational Medicine (IOM) reports a recommended allowable diet (RDA) of 0.9 mg / day, as well as a tolerable intake maximum of 10 mg / day. In the present invention, nanocomposites have a copper content of between approximately 30-150 μg / g. The acrylic material of a prosthetic base has a mass of approximately 10 g, so a prosthesis made of the nanocomposite has maximum copper contents between 0.3-1.5 mg. This suggests that the amount of copper released in the oral cavity should be found below the recommended levels in some of the regulations. In addition, cytoxicity studies of each of the formulated materials were carried out, in order to optimize the nanocomposite's antmicrobial activity based on biotolerable copper levels and indicated by existing regulations.
Desde el punto de vista metodológico se sintetiza el material compuesto mediante diferentes estrategias de síntesis in-situ. En dichas estrategias, el cobre, ya sea como precursor de la posterior nanopartícula o como partícula ya sintetizada, es mezclado con el monómero para en conjunto realizar la polimerización. En una primera estrategia tanto el polímero como la nanopartícula son sintetizados en una misma etapa mediante la adición de un precursor de cobre y el monómero; en la segunda estrategia la nanopartícula ya sintetizada es mezclada con el monómero para su la posterior polimerización. En esta última estrategia se estudió dos formas de nanopartículas de cobre: metálica y de cobre soportado en una matriz cerámica. From the methodological point of view, the composite material is synthesized through different in-situ synthesis strategies. In these strategies, copper, either as a precursor to the subsequent nanoparticle or as a particle already synthesized, is mixed with the monomer to collectively carry out the polymerization. In a first strategy both the polymer and the nanoparticle are synthesized at the same stage by the addition of a copper precursor and the monomer; In the second strategy the nanoparticle already synthesized is mixed with the monomer for subsequent polymerization. In this last strategy, two forms of copper nanoparticles were studied: metallic and copper supported on a ceramic matrix.
Dado que la efectividad antimicrobiana y la toxicidad están relacionadas con la liberación de iones de cobre, se busca encontrar aquella metodología que permita controlar de mejor manera la tasa de liberación de los iones, sin alterar el proceso de polimerización ni las propiedades finales de la resina: mecánicas, estéticas (coloración) y de citocompatibilidad. Since antimicrobial effectiveness and toxicity are related to the release of copper ions, we seek to find that methodology that allows better control of the rate of release of ions, without altering the polymerization process or the final properties of the resin : mechanical, aesthetic (coloring) and cytocompatibility.
DESCRIPCIÓN DETALLADAS DE LAS FIGURAS. DETAILED DESCRIPTION OF THE FIGURES.
La Figúral a muestra una imagen de microscopía SEM de las nanopartículas de cobre (CuNP) sintetizadas in situ en el monómero acrílico, en donde el tamaño promedio de las CuNP es de 40 nm y su naturaleza nanométrica fue también confirmada mediante el plasmón de resonancia superficial detectado por la característica banda de absorción a 593 nm (ver Fig. 1 b). La Fig. 1 b muestra una imagen SEM de nanopartículas de cobre sintetizadas por el método in situ en monómero acrílico (a) y espectro de absorción indicando el plasmón de resonancia superficial. Fig. A shows an SEM microscopy image of the copper nanoparticles (CuNP) synthesized in situ in the acrylic monomer, where the average size of the CuNP is 40 nm and its nanometric nature was also confirmed by surface resonance plasmon. detected by the characteristic absorption band at 593 nm (see Fig. 1b). Fig. 1b shows an SEM image of copper nanoparticles synthesized by the in situ method in acrylic monomer (a) and absorption spectrum indicating the surface resonance plasmon.
Figure imgf000035_0001
Figure imgf000035_0001
La Figura 2a, 2b y 2c muestra la presencia de las nanoaprtícuas de cobre en la matriz acrílica de los nanocompósitos que fue confirmada mediante mapeo elemental EDX, encontrándose una distibución relativamente homogénea del metal sobre toda la matriz polimérica. El análisis FTIR de los materiales indicó que los espectros de los nanocompósitos presentan todas las bandas correspondientes al espectro del PMMA, indicando que la estructura química del polímero no es alterada con la incorporación de las nanopartículas metálicas. En donde, la figura 2a muestra una imagen SEM de nanocomposito CuNP/PMMA, la figura 2b muestra un mapeo elemental EDX confirmando la distribución de cobre en la matriz acrílica; y la figura 2c muestra un análisis FTIR-ATR de acrílico PMMA y materiales nanocompósitos. Figure 2a, 2b and 2c shows the presence of the copper nanoaprtircuas in the acrylic matrix of the nanocomposites that was confirmed by EDX elementary mapping, finding a relatively homogeneous distribution of the metal over the entire polymer matrix. The FTIR analysis of the materials indicated that the spectra of the nanocomposites have all the bands corresponding to the PMMA spectrum, indicating that the chemical structure of the polymer is not altered with the incorporation of the metal nanoparticles. Where, Figure 2a shows a CuNP / PMMA nanocomposite SEM image, Figure 2b shows an EDX elementary mapping confirming the distribution of copper in the acrylic matrix; and Figure 2c shows an FTIR-ATR analysis of PMMA acrylic and nanocomposite materials.
Figure imgf000035_0002
Figure imgf000035_0002
FIGURA 2a FIGURA 2b FIGURA 2c  FIGURE 2a FIGURE 2b FIGURE 2c
Las figura 3a y 3b muestra que los materiales nanocompósitos con diferentes contenidos de CuNP mantienen las propiedades mecánicas originales del acríllco control PMMA. En donde, la figura 3a muestra la propiedad mecánica de resistencia a la flexión del acríllco PMMA y de los nanocompósltos con diferente contenido de CuNP; y la figura 3b muestra la propiedad mecánica del módulo de compresión del acríllco PMMA y de los nanocompósltos con diferente contenido de CuNP: Figures 3a and 3b show that nanocomposite materials with different contents of CuNP maintains the original mechanical properties of the PMMA control acrylic. Wherein, Figure 3a shows the mechanical property of flexural strength of PMMA acrylic and nanocomposts with different CuNP content; and Figure 3b shows the mechanical property of the compression module of PMMA acrylic and nanocomposts with different CuNP content:
Figure imgf000036_0001
Figure imgf000036_0001
FIGURA 3a FIGURE 3a
Figure imgf000036_0002
Figure imgf000036_0002
FIGURA 3b FIGURE 3b
Los resultados de la actividad antimlcrobiana de los materiales nanocompósltos frente a C. albicans fue expresada como una capacidad de inhibición del crecimiento del microorganismo en su superficie respecto al número de colonias crecidas en el material PMMA control sin CuNP, la cual es definida por la siguiente expresión: The results of the antimlcrobial activity of the nanocomposite materials against C. albicans was expressed as an ability to inhibit the growth of the microorganism on its surface with respect to the number of colonies grown in the PMMA control material without CuNP, which is defined by the following expression:
(CFUpfrm^ CFU ^CUNP /PMMA ^) (CFUpfrm ^ CFU ^ CUNP / PMMA ^ )
Capacidad de Inhibición = ~~ rr¡ :— ; x 100 Inhibition Ability = ~~ rr¡ : - ; x 100
Cr  Cr
CFU PMMA : Unidades hormadoras de colonia crecidas en la superficie de acrílico PMMA. CFUPMMA■ Unidades formadoras de colonia crecidas en la superficie de nanocompósito CuNP/PMMA. PMMA CFU: Colony kiln units grown on the PMMA acrylic surface. CFUPMMA ■ Colony forming units grown on the CuNP / PMMA nanocomposite surface.
La Figura 4 muestra la capacidad de inhibición de materiales nanocompósitos frente a C. albicans luego de 48 horas de incubación preparados con diferentes contenidos de CuNP, en donde se observa que los nanocompósitos de acrílico de prótesis preparados poseen un rango de contenido de cobre entre 0,01 5 a 0,068% , y los cuales producen un rango de porcentaje de inhibición entre 65% a 92 %, en donde se obtiene la máxima capacidad de inhibición del crecimiento de C. albicans con un contenido de CuNP de 0,045 %. Figure 4 shows the capacity of inhibition of nanocomposite materials against C. albicans after 48 hours of incubation prepared with different CuNP contents, where it is observed that the acrylic nanocomposites of prepared prostheses have a copper content range between 0 , 01 5 to 0.068%, and which produce a range of percent inhibition between 65% to 92%, where the maximum capacity for growth inhibition of C. albicans with a CuNP content of 0.045% is obtained.
Figure imgf000037_0001
Figure imgf000037_0001
0.015% 0,045% 0,053% 0,060% 0.068%  0.015% 0.045% 0.053% 0.060% 0.068%
Contenido de cobre ¡%¡  Copper content ¡% ¡
FIGURA 4 FIGURE 4
La Figura 5 muestra la capacidad de inhibición de materiales nanocompósitos (CuNP/PMMA) frente a C. Albicans a diferentes tiempos de incubación, en donde se comprobó que el efecto antimicrobiano en la superficie del material se prolonga con el tiempo.
Figure imgf000038_0001
Figure 5 shows the ability to inhibit nanocomposite materials (CuNP / PMMA) against C. albicans at different incubation times, where it was found that the antimicrobial effect on the surface of the material continues over time.
Figure imgf000038_0001
4 7  4 7
Tiempo de incubación [días]  Incubation time [days]
FIGURA 5 FIGURE 5
Con el propósito de dilucidar el posible mecanismo de acción antimicrobiana del material nanocompósito, se analizó la superficie del material mediante espectroscopia XPS La Figura 6 muestra el espectro XPS de la superficie del acrílico nanocompósito CuNP(0,045%)/PMMA. Los resultados del análisis indican que no existen átomos de cobre detectables en la superficie del material; por lo que el efecto antimicrobiano debería ser atribuido fundamentalmente a las cantidades de cobre liberadas al medio producto de la difusión de los iones o nanopartículas de cobre desde la matriz acrílica al medio.  In order to elucidate the possible mechanism of antimicrobial action of the nanocomposite material, the surface of the material was analyzed by XPS spectroscopy. Figure 6 shows the XPS spectrum of the surface of the nanocomposite acrylic CuNP (0.045%) / PMMA. The results of the analysis indicate that there are no detectable copper atoms on the surface of the material; Therefore, the antimicrobial effect should be attributed primarily to the quantities of copper released into the medium due to the diffusion of copper ions or nanoparticles from the acrylic matrix to the medium.
Figure imgf000038_0002
Figure imgf000038_0002
FIGURA 6 FIGURE 6
La Figura 7 muestra la liberación de cobre en función del tiempo desde acrílicos nanocompósitos en saliva artificial (pH 6,5), en donde se observa que los materiales liberan muy bajas concentraciones de cobre al medio, con valores máximos alrededor de 5,8 x10"3 μg/mL después de luego de 35 días de incubación en saliva artificial. Sin embargo, estos bajos niveles de cobre liberados son suficientes para producir el efecto antimicrobiano observado y al mismo tiempo mantener la biocompatibilidad del nuevo material de prótesis. Figure 7 shows the release of copper as a function of time from acrylic nanocomposites in artificial saliva (pH 6.5), where it is observed that the materials release very low concentrations of copper to the medium, with maximum values around 5.8x10 "3 μg / mL after 35 days of incubation in artificial saliva. However, these low Released copper levels are sufficient to produce the observed antimicrobial effect and at the same time maintain the biocompatibility of the new prosthetic material.
Figure imgf000039_0001
Figure imgf000039_0001
Tiempo de incubación (días)  Incubation time (days)
FIGURA 7 FIGURE 7
En la FIGURA 8 se presenta la viabilidad de células fibroblásticas humanas cultivadas a diferentes tiempos de incubación con el material acrílico actual de prótesis (PMMA) y el nanocomposito CuNP/PMMA medida mediante el ensayo de actividad mitocondrial MTS. Se puede observar que la viabilidad celular sobre el nanocomposito CuNP/PMMA es equivalente a la observado sobre el acrílico PMMA actual de prótesis. Estos resultados demuestran que la incorporación de CuNPs en el acrílico no altera sus características de citocompatibilidad. FIGURE 8 shows the viability of human fibroblast cells cultured at different incubation times with the current acrylic prosthesis material (PMMA) and the CuNP / PMMA nanocomposite measured by the MTS mitochondrial activity assay. It can be seen that the cell viability on the CuNP / PMMA nanocomposite is equivalent to that observed on the current PMMA acrylic prosthesis. These results demonstrate that the incorporation of CuNPs in acrylic does not alter its cytocompatibility characteristics.
Figure imgf000040_0001
Figure imgf000040_0001
FIGURA 8 FIGURE 8
En el proceso de preparación de acríllcos antlmlcroblanos se puede también extender en la preparación de diferentes materiales acríllcos de uso dental, tales como resinas de restauración dental, adhesivos para resinas de restauración o brackets ortodónticos, sellantes de fosas y fisuras oclusales así como vidrios ionómeros modificados con resina. Estos materiales son preparados utilizando monómeros acríllcos diferentes al MMA, tales como Bls- GMA, TEGDMA, UDMA, HEMA o PENTA y pueden ser polimerizados mediante fotocurado, autocurado o mediante un sistema dual. En la TABLA 1 se muestran las capacidades de inhibición de la bacteria cariogénlca S. mutans para los diferentes materiales dentales nanocompósltos preparados mediante el proceso ex situ de Incorporación de CuNPs. In the process of preparing anti-mlbranch acrylics, it can also be extended in the preparation of different acrylic materials for dental use, such as dental resins, adhesives for resins or orthodontic brackets, seals of occlusal pits and fissures as well as modified ionomer glasses with resin These materials are prepared using acrylic monomers other than MMA, such as Bls-GMA, TEGDMA, UDMA, HEMA or PENTA and can be polymerized by photo-curing, self-curing or by a dual system. TABLE 1 shows the inhibition capabilities of the cariogenic S. mutans bacteria for the different nanocompost dental materials prepared by the ex situ process of CuNPs Incorporation.
TABLA 1  TABLE 1
Capacidad de inhibición Inhibition ability
Material Dental de S. mutans (%) ± DS  Dental material of S. mutans (%) ± DS
Acríllco de prótesis 97 ± 2 Acrylic prosthesis 97 ± 2
Resina dental restauración 97 ± 2  Dental resin restoration 97 ± 2
Adhesivo dental 99 ± 3  99 ± 3 dental adhesive
Sellante dental 99 ± 3  99 ± 3 dental sealant
Vidrio ionómero 95 + 4 El material acríllco dental nanocompóslto CuNP/PMMA también presentó capacidad de inhibición frente a la bacteria agreggatibacter actinomycetemcomitans (93 % ± 3), un patógeno representativo de la gingivitis y periodontitis. 95 + 4 ionomer glass The CuNP / PMMA nanocompost dental acrylic material also showed inhibitory capacity against the bacterium aggregatibacter actinomycetemcomitans (93% ± 3), a pathogen representative of gingivitis and periodontitis.
El proceso de preparación del nanocompósito CuNP/PMMA puede ser también utilizado para la fabricación de cemento óseo con propiedades antimicrobianas. El cemento óseo a base de PMMA autocurable es utilizado en ortopedia para la fijación de prótesis de caderas, rodilla, hombro y otras prótesis articulares. El cemento óseo a base de CuNP/PMMA presentó una capacidad de inhibición de 94 % ± 3 frente a la bacteria Staphylococcus aureus, principal patógeno responsable de las infecciones periprotésicas. The CuNP / PMMA nanocomposite preparation process can also be used for the manufacture of bone cement with antimicrobial properties. Self-healing PMMA-based bone cement is used in orthopedics for the fixation of hip, knee, shoulder and other joint prostheses. The bone cement based on CuNP / PMMA showed a capacity of inhibition of 94% ± 3 against the Staphylococcus aureus bacteria, the main pathogen responsible for periprosthetic infections.
La presente invención está orientada a desarrollar un material polimérico con nanopartículas de cobre (CuNP), para lo cual se sintetizó el material compuesto mediante diferentes estrategias de síntesis ex situ e in-situ. En donde, el compósito puede ser preparado mediante el m étodo ex situ, i nco rpo rando las partícu las de Cu N Ps/Zeo o nanopartícu las de cobre (Cu N P) preparadas ex situ por éste u otros métodos . The present invention is aimed at developing a polymeric material with copper nanoparticles (CuNP), for which the composite material was synthesized by different ex situ and in situ situ synthesis strategies. Wherein, the compound can be prepared by the ex situ method, including by dividing the Cu N Ps / Zeo particles or copper nanoparticles (Cu N P) prepared ex situ by this or other methods.
En todas estas estrategias, el cobre, ya sea como precursor de la posterior nanopartícula o como partícula ya sintetizada; es mezclado con el monómero (PMMA) para en conjunto realizar la polimerización. En una primera estrategia tanto el polímero como la nanopartícula se sintetizaron en una misma etapa mediante la adición de un precursor de una sal orgánica de cobre [Cu(CH3COO)2] y el monómero; en la segunda estrategia la nanopartícula sintetizada fue mezclada con el monómero para su la posterior polimerización. En esta última estrategia se busca estudiar dos formas de nanopartículas de cobre: metálica y de cobre soportado en una matriz cerámica. Debido a que la efectividad antimicrobiana y la toxicidad están relacionadas con la liberación de iones de cobre, se pretende encontrar aquella metodología que permita controlar de mejor manera la tasa de liberación de los iones, sin alterar el proceso de polimerización ni las propiedades finales de la resina, tal como mecánicas, estéticas (coloración) y de citocompatibilidad. EJEMPLOS In all these strategies, copper, either as a precursor to the subsequent nanoparticle or as a particle already synthesized; It is mixed with the monomer (PMMA) to collectively carry out the polymerization. In a first strategy both the polymer and the nanoparticle were synthesized at the same stage by adding a precursor of an organic copper salt [Cu (CH 3 COO) 2 ] and the monomer; In the second strategy the synthesized nanoparticle was mixed with the monomer for subsequent polymerization. In this last strategy, we seek to study two forms of copper nanoparticles: metallic and copper supported on a ceramic matrix. Because antimicrobial effectiveness and toxicity are related to the release of copper ions, it is intended to find that methodology that allows better control of the rate of release of ions, without altering the polymerization process or the final properties of the resin, such as mechanical, aesthetic (coloring) and cytocompatibility. EXAMPLES
EJEMPLO 1. EXAMPLE 1.
En este ejemplo, se detalla la preparación de nanocompósltos CuNP/PMMA mediante una síntesis in situ del material nanocompósitoutilizando polimerización de auto o termocurado. En donde se utiliza soluciones acuosas de acetato de cobre [Cu(CH3COO)2] de distinta concentración (0,1 -0,8 M), preferentemente entre 0,6-0,7 M, para lo cual 100 μΙ_ de la solución de cobre (Cu2+) se agrega sobre 2 ml_ de etanol absoluto, a la mezcla resultante se agrega bajo constante agitación 2 ml_ del monómero dental líquido de metilmetacrilato de auto o termocurado. La solución resultante se mantiene con agitación constante a temperaturas entre 50 - 70 °C hasta la formación de las nanopartículas (CuNP), lo cual se visualiza por la aparición de la coloración rojiza que toma la mezcla de reacción. Posteriormente, dicha solución de monómero líquido cargada con CuNPs, se mezcla con acrílico dental en polvo en una proporción 3:2 de masa de acrílico:volumen de monómero (PMMA) para llevar a cabo la reacción de polimerización en condiciones de auto o termocurado según corresponda. In this example, the preparation of CuNP / PMMA nanocomposts is detailed by an in situ synthesis of the nanocomposite material using self-curing or thermosetting polymerization. Where aqueous solutions of copper acetate [Cu (CH 3 COO) 2 ] of different concentration (0.1-0.8 M) are used, preferably between 0.6-0.7 M, for which 100 μΙ_ of The copper solution (Cu 2+ ) is added over 2 ml_ of absolute ethanol, to the resulting mixture is added under constant stirring 2 ml_ of the liquid dental monomer of methyl or methacrylate methyl methacrylate. The resulting solution is maintained with constant stirring at temperatures between 50-70 ° C until the formation of the nanoparticles (CuNP), which is visualized by the appearance of the reddish coloration taken by the reaction mixture. Subsequently, said solution of liquid monomer loaded with CuNPs, is mixed with powdered dental acrylic in a 3: 2 ratio of acrylic mass: monomer volume (PMMA) to carry out the polymerization reaction under auto or thermoset conditions according to correspond.
EJEMPLO 2. EXAMPLE 2
En este ejemplo, se detalla la preparación de compósitos CuNP/PMMA utilizando CuNPS soportadas. El material compósito se preparó usando también Cu N Ps previamente soportadas en partícu l as de u n materi al cerám ico . E l uso de Cu N Ps i ncl u idas e n partícu las cerám icas podría mejorar las propiedades de coloración del compósito : así como ofrecer una cinética de liberación de cobre diferente desde el material . Además: al tratarse de un soporte cerámico : la densidad será menor que en el caso de partículas metál icas : por lo que problemas de estabi lidad y decantación podrán ser resueltos . Como materiales de soporte se usaron partículas de zeolita (al umi nosil icato cristalino nanoporoso) y nanopartículas de sílice, para lo cual, se uti lizaron u na zeol ita natural de procedencia nacional (MO R) y nanopartícu las de síl ice de 1 00 n m comerciales . Las Cu N Ps serán form adas in situ en el m aterial , para este propósito cierta masa de MOR fue contactada con una solución de acetato de cobre 0,1 M durante 24 h a temperatura ambiente. Una vez completado el periodo de intercambio iónico, la zeolita fue separada y lavada mediante repetidos ciclos de centrifugación/dispersión. El material obtenido fue luego dispersado en una solución reductora de almidón/ácido ascórbico, y sometida a microondas por ciertos segundos. Este sistema de formación de CuNPs en biopolímeros fue desarrollado por nuestro equipo de laboratorio, como un método bajo el concepto de "Química Verde" para la síntesis de nanopartículas metálicas más benignas, y compatible con aplicaciones biomédicas. Las partículas de CuNPs/MOR fueron separadas, lavadas y secadas para ser usadas posteriormente en el proceso de preparación del compósito CuNP/PMMA. El compósito fue preparado mediante el método ex situ antes descrito, incorporado las partículas deshidratadas de CuNPs/MOR en el monómero líquido de metilmetacrilato. In this example, the preparation of CuNP / PMMA composites using supported CuNPS is detailed. The composite material was also prepared using Cu N Ps previously supported in part of a ceramic material. The use of ceramic particles in particular could improve the coloring properties of the compound : as well as offering a different copper release kinetics from the material. In addition : as it is a ceramic support : the density will be lower than in the case of metallic particles : therefore stability and decantation problems can be solved. Zeolite particles (al um nosil nanoporous crystalline icato) and silica nanoparticles were used as support materials, for which, a natural zeolite of national origin (MO R) and nanoparticles of 1,00 ice ice were used commercial nm. The Cu N Ps will be formed in situ in the material, for this Purpose certain mass of MOR was contacted with a 0.1 M copper acetate solution for 24 h at room temperature. After the ion exchange period was completed, the zeolite was separated and washed by repeated centrifugation / dispersion cycles. The material obtained was then dispersed in a starch / ascorbic acid reducing solution, and microwaved for certain seconds. This system of formation of CuNPs in biopolymers was developed by our laboratory team, as a method under the concept of "Green Chemistry" for the synthesis of more benign metal nanoparticles, and compatible with biomedical applications. The CuNPs / MOR particles were separated, washed and dried for later use in the process of preparing the CuNP / PMMA compound. The compound was prepared by the ex situ method described above, incorporating the dehydrated CuNPs / MOR particles in the liquid methyl methacrylate monomer.
EJEMPLO 3. EXAMPLE 3
En este ejemplo, se detalla la preparación de compósitos CuNP/PMMA mediante un método ex situ de incorporación de CuNP en acrílico dental de auto o termocurado, en donde se utilizan CuNPs de 5 nm en polvo y disponibles comercialmente (Nanotec SpA, Chile). Las CuNPs fueron adicionadas al monómero líquido metilmetacrilato (4 mL) de auto o termocurado, masas de CuNPs en el rango de 0,79 - 6,28 mg, seguidamente se dispersan en ultrasonido por 10 minutos y luego se mezclan con acrílico dental en polvo en una proporción 3:2 de masa de acrílico/volumen de monómero (polimetilmetacrilato: con iniciador incorporado) para dar lugar a la reacción de polimerización), posteriormente se efectúa la polimerización en condiciones de auto o termocurado. In this example, the preparation of CuNP / PMMA composites is detailed by means of an ex situ method of incorporating CuNP into self-curing or acrylic dental acrylic, where 5 nm CuNPs are used in powder and commercially available (Nanotec SpA, Chile). The CuNPs were added to the methyl or methacrylate liquid monomer (4 mL) of auto or thermosetting, CuNP masses in the range of 0.79 - 6.28 mg, then dispersed in ultrasound for 10 minutes and then mixed with powdered dental acrylic in a 3: 2 ratio of acrylic mass / monomer volume (polymethylmethacrylate : with incorporated initiator) to give rise to the polymerization reaction), the polymerization is subsequently carried out under auto or thermoset conditions.
EJEMPLO 4 EXAMPLE 4
En este ejemplo se describe la evaluación in vitro de las propiedades antimicrobianas de los nanocompositos CuNPs/PMMA, para lo cual se desarrolla un estudio microbiologico utilizando una cepa ATCC 90029 de Candida albicans, a partir de la cual se preparan caldos de cultivos con una concentración 0,5 de Mcfarland (1 -5 x106 UFC /mi). En la suspensión del microorganismo se incuba las muestras del material nanocompósito CuNPs/PMMA preparadas con diferentes contenidos de CuNPs, así como de muestras del material acrílico sin CuNPs como control (PMMA). El período de incubación es inicialmente de 48 horas a 37 SC en condiciones de aerobiosis. El efecto antimicrobiano de los materiales se evalúa mediante recuento de colonias en el caldo sobrenadante así como en la superficie de los materiales. Para el primer caso, se siembran diluciones del caldo de cultivo en placas de agar Sabouraud y se incuban por 48 h a 37 °C. Por otro lado, los microorganismos adheridos en la superficie del material, se remueven mediante una solución de surfactante inocuo, para luego ser sembradas e incubadas en agar y realizar el recuento de UFC. This example describes the in vitro evaluation of the antimicrobial properties of CuNPs / PMMA nanocomposites, for which a microbiological study using a strain ATCC 90029 of Candida albicans, from which broths of cultures with a concentration of 0.5 Mcfarland are prepared (1-5 x10 6 CFU / mi). In the suspension of the microorganism, the samples of the CuNPs / PMMA nanocomposite material prepared with different CuNPs contents are incubated, as well as samples of the acrylic material without CuNPs as control (PMMA). The incubation period is initially 48 hours at 37 S C under aerobic conditions. The antimicrobial effect of the materials is evaluated by colony counting in the supernatant broth as well as on the surface of the materials. For the first case, dilutions of the culture broth are seeded in Sabouraud agar plates and incubated for 48 h at 37 ° C. On the other hand, the microorganisms adhered to the surface of the material, are removed by means of a harmless surfactant solution, to then be seeded and incubated in agar and perform the CFU count.
Adicionalmente, se evaluó el efecto antimicrobiano de los materiales por un período prolongado de 10 días en contacto con los microorganismos. Additionally, the antimicrobial effect of the materials was evaluated for a prolonged period of 10 days in contact with the microorganisms.
EJEMPLO 5 EXAMPLE 5
En este ejemplo se ensayó la liberación de cobre desde el material, con el propósito de explicar el mecanismo de actividad antimicrobiana de los nanocompósitos. Estos ensayos se realizaron sumergiendo una pieza de cada tipo de nanocompósito CuNP/PMMA en saliva artificial (KCI- NaCI-CaCI2-2H20-NaH2P04-2H20-Na2S-9H20-urea) pH 6,5 a 37 SC, cada ciertos intervalos de tiempo se tomó una muestra del líquido sobrenadante, fracción que fue reemplazada con saliva artificial fresca. La concentración de cobre total en las alícuotas recolectadas se determinó mediante espectrometría de emisión atómica de plasma acoplado inductivamente (ICP-AES). A partir de estas concentraciones se determinó las cantidades liberadas del metal en función del tiempo. EJEMPLO 6 In this example, the release of copper from the material was tested, in order to explain the mechanism of antimicrobial activity of nanocomposites. These tests were performed by immersing a piece of each type of CuNP / PMMA nanocomposite in artificial saliva (KCI-NaCI-CaCI 2 -2H 2 0-NaH 2 P0 4 -2H 2 0-Na 2 S-9H 2 0-urea) pH 6.5 to 37 S C, every certain time intervals a sample of the supernatant liquid was taken, a fraction that was replaced with fresh artificial saliva. The total copper concentration in the collected aliquots was determined by inductively coupled plasma atomic emission spectrometry (ICP-AES). From these concentrations the quantities released from the metal were determined as a function of time. EXAMPLE 6
En este ejemplo se ensayó la cltocompatlbllldad de los materiales nanocompósitos, para lo cual se evaluó mediante su incubación en cultivos de células fibroblásticas. La viabilidad celular se determinó mediante el ensayo espectrofotométrico de actividad mitocondrial MTS (3-(4,5- dimetiltiazol-2-il) 5-(3-carboximetoxifenil) -2-(4-sulfofenil)-2H-tetrazolio), durante 3, 5 y 10 días de incubación con el material. In this example, the cltocompatibility of nanocomposite materials was tested, for which it was evaluated by incubation in fibroblast cell cultures. Cell viability was determined by the MTS (3- (4,5-dimethylthiazol-2-yl) 5- (3-carboxymethoxyphenyl) -2- (4-sulfophenyl) -2H-tetrazolium) mitochondrial activity spectrophotometric assay. , 5 and 10 days of incubation with the material.
EJEMPLO 7 EXAMPLE 7
En el presente ejemplo se realizó la fabricación de prótesis dentales utilizando el material nanocompósito previamente optimizado en función de su composición, propiedades antimicrobianas, mecánicas, estéticas (color) y de citocompatibilidad. Para dicho propósito se usaron dos protocolos diferentes de fabricación utilizados normalmente por los laboratorios dentales. Las prótesis se fabricaron en las instalaciones de los laboratorios dentales, de acuerdo a protocolos establecidos con respecto a las condiciones de temperatura, tiempo y presión de termocurado; así como del tipo de cubetas, materiales de impresión, muflas, y otros elementos utilizados para el diseño de la prótesis de acuerdo con las características del paciente. Las prótesis fabricadas se evalúan de acuerdo a criterios odontológicos con respecto a las propiedades mecánicas de la base acrílica, estabilidad de los dientes artificiales, características estéticas, entre otros. In the present example, the manufacturing of dental prostheses was performed using the nanocomposite material previously optimized based on its composition, antimicrobial, mechanical, aesthetic (color) and cytocompatibility properties. For this purpose, two different manufacturing protocols normally used by dental laboratories were used. The prostheses were manufactured in the facilities of the dental laboratories, according to established protocols regarding the temperature conditions, time and pressure of thermosetting; as well as the type of cuvettes, printing materials, muffles, and other elements used for the design of the prosthesis according to the characteristics of the patient. Manufactured prostheses are evaluated according to dental criteria with respect to the mechanical properties of the acrylic base, stability of artificial teeth, aesthetic characteristics, among others.
EJEMPLO 8 EXAMPLE 8
En este ejemplo, se detalla la preparación de nanocompósitos CuNP/acrílico mediante un método ex situ de incorporación de CuNPs en resina de restauración dental. Las CuNPs en polvo son incorporadas en un sistema de fotocurado o dual a base de monómeros acrílicos, tales como Bis-GMA, TEGDMA, UDMA u otro, el cual puede contener un micro o nanorelleno a base de partículas cerámicas. Se incorporan concentraciones de CuNPs, preferentemente en el rango 0,015 - 0,045 % en peso. La mezcla resultante se trata mediante ultrasonido por 1 0 minutos, para luego efectuar la reacción de polimerización aplicando luz L.E.D. por 40 segundos en presencia de canforquinona como fotoiniciador. In this example, the preparation of CuNP / acrylic nanocomposites is detailed by an ex situ method of incorporating CuNPs in dental restoration resin. Powdered CuNPs are incorporated into a photocurate or dual system based on acrylic monomers, such as Bis-GMA, TEGDMA, UDMA or other, which may contain a micro or nanofill based on ceramic particles. CuNPs concentrations are incorporated, preferably in the range 0.015 - 0.045% by weight. The resulting mixture is treated by ultrasound by 1.0 minutes, then carry out the polymerization reaction by applying LED light for 40 seconds in the presence of camphorquinone as a photoinitiator.
EJEMPLO 9 EXAMPLE 9
En este ejemplo, se detalla la preparación de nanocompositos CuNP/acrílico la preparación de nanocompositos CuNP/ mediante un método ex situ de incorporación de CuNPs en un sistema adhesivo de resina de restauración dental. Las CuNPs en polvo son incorporadas en sistemas adhesivos a base de monómeros acrílicos tales como UDMA o PENTA de fotocurado o dual. Se incorporan concentraciones de CuNPs preferentemente en el rango 0,015 - 0,045 % en peso. La mezcla resultante se trata mediante ultrasonido por 30 segundos, para luego efectuar la reacción de polimerización aplicando luz L.E.D. por 10 - 30 segundos en presencia de canforquinona como fotoiniciador o mediante polimerización dual. In this example, the preparation of CuNP / acrylic nanocomposites is detailed, the preparation of CuNP / nanocomposites by means of an ex situ method of incorporating CuNPs into a dental restoration resin adhesive system. Powdered CuNPs are incorporated into adhesive systems based on acrylic monomers such as UDMA or PENTA photocurate or dual. Concentrations of CuNPs are preferably incorporated in the range 0.015-0.045% by weight. The resulting mixture is treated by ultrasound for 30 seconds, to then carry out the polymerization reaction by applying light L.E.D. for 10-30 seconds in the presence of camphorquinone as a photoinitiator or by dual polymerization.
EJEMPLO 10 EXAMPLE 10
En este ejemplo, se detalla la preparación de nanocompositos CuNP/acrílico utilizando acrílico de adhesivos ortodonticos mediante un método ex situ de incorporación de CuNPs. Las CuNPs en polvo son incorporadas en sistemas de adhesivos para la cementación de brackets ortodonticos a base de monómeros acrílicos tales como TEGDMA, Bis-GMA, UDMA, o HEMA foto o autopolimerizables. Se incorporan concentraciones de CuNPs preferentemente en el rango 0.01 5-0.045 % en peso. La mezcla resultante se trata mediante ultrasonido por 30 segundos, para luego efectuar la reacción de polimerización aplicando luz L.E.D. por 10 segundos en presencia de canforquinona como fotoiniciador o mediante autopolimerización. In this example, the preparation of CuNP / acrylic nanocomposites using orthodontic adhesive acrylic by an ex situ method of incorporating CuNPs is detailed. Powdered CuNPs are incorporated into adhesive systems for the cementation of orthodontic brackets based on acrylic monomers such as TEGDMA, Bis-GMA, UDMA, or HEMA photo or self-curing. Concentrations of CuNPs are preferably incorporated in the range 0.01 5-0.045% by weight. The resulting mixture is treated by ultrasound for 30 seconds, to then carry out the polymerization reaction by applying light L.E.D. for 10 seconds in the presence of camphorquinone as a photoinitiator or by self-polymerization.
EJEMPLO 11 EXAMPLE 11
En este ejemplo, se detalla la preparación de nanocompositos CuNP/acrílico mediante un método ex situ de incorporación de CuNPs utilizando vidrio ionomero modificado con resina acrílica fotopolimerizable utilizado como agente cementante y material restaurador en dientes temporales y como provisional en dientes permanentes. Las CuNPs en polvo son incorporadas en el vidrio ionomero líquido de foto o autocurado a concentraciones preferentemente en el rango 0.01 5-0.045 % en peso. Lamezcla resultante se trata mediante ultrasonido por 30 segundos, para luego efectuar la reacción de polimerización aplicando luz L.E.D. por 10 -30 segundos en presencia de canforquinona como fotoiniciador o a través de polimerización de autocurado. In this example, the preparation of CuNP / acrylic nanocomposites is detailed by an ex situ method of incorporating CuNPs using ionomer glass modified with photopolymerizable acrylic resin used as cementing agent and restorative material in teeth temporary and as provisional in permanent teeth. Powdered CuNPs are incorporated into the liquid ionomer glass of photo or self-curing at concentrations preferably in the range 0.01 5-0.045% by weight. The resulting mixture is treated by ultrasound for 30 seconds, to then carry out the polymerization reaction by applying LED light for 10-30 seconds in the presence of camphorquinone as a photoinitiator or through self-curing polymerization.
EJEMPLO 12 EXAMPLE 12
En este ejemplo, se detalla la preparación de nanocompósitos CuNP/acrílico mediante un método ex situ de incorporación de CuNPs en sellantes de fosas y fisuras aplicado a superficies oclusales de los dientes molares que son especialmente susceptibles a la acumulación de placa bacteriana y al consecuente desarrollo de caries. Las CuNPs en polvo son incorporadas en el vidrio sellantes a base de monómeros acrílicos tales como Bis-GMA o TEGDMA de foto o autocurado a concentraciones preferentemente en el rango 0.015-0.045 % en peso. La mezcla resultante se trata mediante ultrasonido por 30 segundos, para luego efectuar la reacción de polimerización aplicando luz L.E.D. por 10 -30 segundos en presencia de canforquinona como fotoiniciador o a través de polimerización de autocurado. In this example, the preparation of CuNP / acrylic nanocomposites is detailed by an ex situ method of incorporating CuNPs in pit and fissure sealants applied to occlusal surfaces of molar teeth that are especially susceptible to bacterial plaque buildup and subsequent development. of caries. Powdered CuNPs are incorporated into the glass sealants based on acrylic monomers such as Bis-GMA or TEGDMA photo or self-curing at concentrations preferably in the range 0.015-0.045% by weight. The resulting mixture is treated by ultrasound for 30 seconds, to then carry out the polymerization reaction by applying light L.E.D. for 10 -30 seconds in the presence of camphorquinone as a photoinitiator or through self-curing polymerization.
EJEMPLO 13 EXAMPLE 13
En este ejemplo, se detalla la preparación de compósitos CuNP/PMMA mediante un método ex situ de incorporación de CuNP en acrílico de cemento óseo utilizado en la fijación de prótesis ortopédicas, tales como de cadera, rodilla, hombro y otras prótesis articulares. Las CuNPs son incorporadas en 4 mL de la fracción líquida monómero/activador de autocurado en cantidades de 0,79 - 6,28 mg, seguidamente se dispersan en ultrasonido por 1 0 minutos y luego se mezclan con acrílico óseo en polvo en una proporción 3 : 2 masa de acrílico (gramos): volumen de monómero (mL). Posteriormente se efectúa la polimerización en condiciones de autocurado. In this example, the preparation of CuNP / PMMA composites is detailed by an ex situ method of incorporating CuNP into bone cement acrylic used in the fixation of orthopedic prostheses, such as hip, knee, shoulder and other joint prostheses. The CuNPs are incorporated in 4 mL of the liquid monomer / autocuration activator fraction in amounts of 0.79 - 6.28 mg, then dispersed in ultrasound for 10 minutes and then mixed with powdered bone acrylic in a proportion 3 : 2 acrylic mass (grams): monomer volume (mL). Subsequently polymerization is carried out under self-curing conditions.

Claims

REIVINDICACIONES
1 . Método de preparación in situ de materiales acrílicos dentales y ortopédicos con propiedades antimicrobianas mediante tecnología de nanopartículas de cobre (CuNPs), CARACTERIZADO porque comprende las siguientes etapas: one . In situ preparation method of dental and orthopedic acrylic materials with antimicrobial properties using copper nanoparticle technology (CuNPs), CHARACTERIZED because it comprises the following stages:
a. - adicionar soluciones acuosas de acetato de cobre [Cu(CH3COO)2] de distinta concentración (0,1 a 0,8 M), preferentemente entre 0,6 a 0,7 M, para lo cual 100 μΙ_ de la solución de cobre (Cu2+) se agrega sobre 2 ml_ de etanol absoluto al 95 %; to. - add aqueous solutions of copper acetate [Cu (CH 3 COO) 2 ] of different concentration (0.1 to 0.8 M), preferably between 0.6 to 0.7 M, for which 100 μΙ_ of the solution Copper (Cu 2+ ) is added over 2 ml_ of 95% absolute ethanol;
b. - adicionar sobre agitación 2 ml_ del monómero dental líquido metilmetacrilato (PMMA) sobre la solución alcohólica del punto (a) bajo constante agitación y a temperatura ambiente;  b. - add 2 ml_ of the methyl dental methacrylate liquid monomer (PMMA) on the alcohol solution of point (a) under constant stirring and at room temperature;
c- mantener la solución resultante en (b) bajo agitación constante a temperatura entre 50 a 70 SC, hasta la formación de las nanopartículas CuNPs de una coloración rojiza; c- maintaining the resulting solution in (b) under constant stirring at a temperature between 50 to 70 S C, until the formation of CuNPs nanoparticles of a reddish coloration;
d. - mezclar la solución de monómero líquido cargada con CuNPs obtenida en (c) con cierta una masa del acrílico dental en polvo (polimetilmetacrilato) en una proporción 3/2 de masa de acrílico/volumen de monómero (PMMA) para dar lugar a la reacción de polimerización; y  d. - mixing the solution of liquid monomer loaded with CuNPs obtained in (c) with a certain mass of the dental acrylic powder (polymethylmethacrylate) in a ratio 3/2 of acrylic mass / monomer volume (PMMA) to give rise to the reaction of polymerization; Y
e. - depositar en moldes de teflón o en mufla dental la mezcla obtenida en (d) para completar el proceso de auto o termocurado  and. - deposit the mixture obtained in (d) in Teflon or dental muffle molds to complete the auto or thermosetting process
2. Método de preparación ex situ de materiales acrílicos dentales y ortopédicos según la reivindicación 1 , CARACTERIZADO porque comprende las siguientes etapas ex situ: 2. Method of ex situ preparation of dental and orthopedic acrylic materials according to claim 1, CHARACTERIZED because it comprises the following ex situ steps:
a. mezclar partícu las de zeolita natural o si ntética (al um inosil icato cristalino nanoporoso) y una sol ución acuosa de acetato de cobre [Cu (CH3COO)2] de concentración 0, 1 M en proporción de 0 ,5 (g ramos)/1 00 (m L) de m asa de zeol ita ; to. mix particles of natural or synthetic zeolite (to the nanoporous crystalline inosyl um) and an aqueous solution of copper acetate [Cu (CH 3 COO) 2 ] with a concentration of 0.1 M in a proportion of 0.5 (g branches) ) / 1 00 (m L) of m zeol ita handle;
b. separar y pu rificar la zeol ita m ediante repetidos ciclos de centrifugación/dispersión ;  b. separate and purify the zeol it by repeated centrifugation / dispersion cycles;
c. secar la zeol ita modificada con cobre a 80°C por dos horas o mediante l iofi l ización . C. Dry the modified zeol ita with copper at 80 ° C for two hours or by Iofi lization.
d. dispersar e l material obten ido e n la etapa (b) e n u na solución reductora de alm idón/ácido ascórbico de concentración al 1 0%;  d. Disperse the material obtained in step (b) in a reducing solution of ascorbic acid / concentration of 1.0%;
e. someter a calentam iento baj o m icroondas la suspensión de zeol ita (Zeo) obten ida en (d) durante 60 seg u ndos uti lizando i ntervalos de 20 segu ndos ; y  and. heat the zeol ita (Zeo) suspension obtained in (d) for 60 seconds using 20-second intervals; Y
f . separar y l avar l as partículas de Cu N Ps/Zeo para ser usadas posteriormente en el proceso de preparación del compósito Cu N P/PMMA.  f. Separate and guarantee the particles of Cu N Ps / Zeo for later use in the process of preparing the Cu N P / PMMA compound.
3. Método de preparaci ón segú n reivindicaciones 1 y 2 , CARACTE RIZADO porque preferentemente las concentraciones de las sol uciones acuosas de acetato de cobre [Cu(CH3COO)2] están entre 0,6 a 0,7 M. 3. Method of preparation according to claims 1 and 2, KIND CHARACTER because preferably the concentrations of the aqueous solutions of copper acetate [Cu (CH 3 COO) 2 ] are between 0.6 to 0.7 M.
4. Material acrílico dental y ortopédico con propiedades antimicrobianas mediante tecnología de nanopartículas de cobre (CuNPs) obtenido según cualquiera de las reivindicaciones 1 ó 2, CARACTERIZADO porque comprende un dispositivo médico o dental, material o implante; y una cantidad antimicrobiana de nanopartículas de cobre (CuNP) difundidas en el mismo o dispuesto sobre el mismo. 4. Dental and orthopedic acrylic material with antimicrobial properties by means of copper nanoparticle technology (CuNPs) obtained according to any of claims 1 or 2, CHARACTERIZED because it comprises a medical or dental device, material or implant; and an antimicrobial amount of copper nanoparticles (CuNP) diffused therein or disposed thereon.
5. Material acrílico de acuerdo con la reivindicación 4, CARACTERIZADO porque comprende un material polimérico que incorpora nanopartículas de cobre. 5. Acrylic material according to claim 4, CHARACTERIZED in that it comprises a polymeric material incorporating copper nanoparticles.
6. Material acrílico de acuerdo con la reivindicación 4, CARACTERIZADO porque las nanopartículas de cobre (CuNPs) poseen un diámetro de entre 40 a 100 nm. 6. Acrylic material according to claim 4, CHARACTERIZED because the copper nanoparticles (CuNPs) have a diameter between 40 to 100 nm.
7. Material acrílico de acuerdo con la reivindicación 4, CARACTERIZADO porque el material polimérico es polimetilmetacrilato (PMMA). 7. Acrylic material according to claim 4, CHARACTERIZED in that the polymeric material is polymethylmethacrylate (PMMA).
8. Material acrílico de acuerdo con la reivindicación 4, CARACTERIZADO porque las nanopartículas de cobre (CuNP) están recubiertos con metilmetacrilato (PMMA). 8. Acrylic material according to claim 4, CHARACTERIZED in that the copper nanoparticles (CuNP) are coated with methyl methacrylate (PMMA).
9. Material acrílico de acuerdo con la reivindicación 4, CARACTERIZADO porque el material es una prótesis dental removible o fija. 9. Acrylic material according to claim 4, CHARACTERIZED in that the material is a removable or fixed dental prosthesis.
10. Material acrílico de acuerdo con la reivindicación 4, CARACTERIZADO porque el material es un adhesivo de resina dental.  10. Acrylic material according to claim 4, CHARACTERIZED in that the material is a dental resin adhesive.
1 1 . Material acrílico de acuerdo con la reivindicación 4, CARACTERIZADO porque el material es un sellante dental de fosas y fisuras. eleven . Acrylic material according to claim 4, CHARACTERIZED because the material is a pit and fissure dental sealant.
12. Material acrílico de acuerdo con la reivindicación 4, CARACTERIZADO porque el material es un adhesivo ortodóncico. 12. Acrylic material according to claim 4, CHARACTERIZED in that the material is an orthodontic adhesive.
13. Material acrílico de acuerdo con la reivindicación 4, CARACTERIZADO porque el material es un vidrio ionómero. 13. Acrylic material according to claim 4, CHARACTERIZED in that the material is an ionomer glass.
14. Material acrílico de acuerdo con la reivindicación 4, CARACTERIZADO porque el material es un cemento óseo. 14. Acrylic material according to claim 4, CHARACTERIZED in that the material is a bone cement.
15. Uso del material acrílico antimicrobianos para prótesis dentales removibles (PDR) basados en nanopartículas de cobre (CuNPs) de acuerdo con las reivindicaciones previas, CARACTERIZADO porque es útil en contra del patógeno oral C. albicans responsable de la estomatitis subprótesica, Streptococcus mutans, bacteria responsable de la formación de caries, así como para Staphylococcus aureus que genera infecciones periprotésicas. 15. Use of the antimicrobial acrylic material for removable dentures (PDR) based on copper nanoparticles (CuNPs) according to the previous claims, CHARACTERIZED because it is useful against the oral pathogen C. albicans responsible for subprothetic stomatitis, Streptococcus mutans, bacteria responsible for the formation of caries, as well as for Staphylococcus aureus that generates periprosthetic infections.
PCT/CL2016/050079 2015-12-30 2016-12-29 Method for producing orthopaedic and dental acrylic materials having antimicrobial properties, using copper nanoparticle technology WO2017113030A1 (en)

Priority Applications (4)

Application Number Priority Date Filing Date Title
EP16880234.6A EP3461335A4 (en) 2015-12-30 2016-12-29 Method for producing orthopaedic and dental acrylic materials having antimicrobial properties, using copper nanoparticle technology
MX2018008122A MX2018008122A (en) 2015-12-30 2016-12-29 Method for producing orthopaedic and dental acrylic materials having antimicrobial properties, using copper nanoparticle technology.
US16/067,053 US11134687B2 (en) 2015-12-30 2016-12-29 Preparation process of dental and orthopedic acrylic materials with antimicrobial properties using copper nanoparticle technology
US17/404,858 US20210400984A1 (en) 2015-12-30 2021-08-17 Antimicrobial adhesive composition with copper nanoparticles for dentures

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CL2015003781A CL2015003781A1 (en) 2015-12-30 2015-12-30 Process of preparation of dental and orthopedic acrylic materials with antibacterial properties using copper nanoparticle technology
CL3781-2015 2015-12-30

Related Child Applications (2)

Application Number Title Priority Date Filing Date
US16/067,053 A-371-Of-International US11134687B2 (en) 2015-12-30 2016-12-29 Preparation process of dental and orthopedic acrylic materials with antimicrobial properties using copper nanoparticle technology
US17/404,858 Division US20210400984A1 (en) 2015-12-30 2021-08-17 Antimicrobial adhesive composition with copper nanoparticles for dentures

Publications (1)

Publication Number Publication Date
WO2017113030A1 true WO2017113030A1 (en) 2017-07-06

Family

ID=56610121

Family Applications (2)

Application Number Title Priority Date Filing Date
PCT/CL2016/050079 WO2017113030A1 (en) 2015-12-30 2016-12-29 Method for producing orthopaedic and dental acrylic materials having antimicrobial properties, using copper nanoparticle technology
PCT/IB2022/057710 WO2023021440A1 (en) 2015-12-30 2022-08-17 Antimicrobial adhesive composition with copper nanoparticles for dentures

Family Applications After (1)

Application Number Title Priority Date Filing Date
PCT/IB2022/057710 WO2023021440A1 (en) 2015-12-30 2022-08-17 Antimicrobial adhesive composition with copper nanoparticles for dentures

Country Status (7)

Country Link
US (2) US11134687B2 (en)
EP (1) EP3461335A4 (en)
AR (1) AR126809A1 (en)
CL (1) CL2015003781A1 (en)
CO (1) CO2024003209A2 (en)
MX (1) MX2018008122A (en)
WO (2) WO2017113030A1 (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CL2015003781A1 (en) * 2015-12-30 2016-06-03 Univ Chile Process of preparation of dental and orthopedic acrylic materials with antibacterial properties using copper nanoparticle technology

Citations (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3476854A (en) 1966-08-08 1969-11-04 Coe Lab Inc Antifungal resinous dental compositions and articles
US4332791A (en) 1980-04-29 1982-06-01 Blendax-Werke R. Schneider Gmbh & Co. Toothpaste active against plaque comprising a copper compound and a silica polishing agent
EP0081962A2 (en) 1981-12-08 1983-06-22 Warner-Lambert Company Denture cleansing composition
EP0471396A1 (en) 1990-08-16 1992-02-19 Unilever N.V. Dental compositions containing stabilized copper
EP0400080B1 (en) 1988-02-11 1992-09-16 Btg International Limited Denture protection
EP1003791A1 (en) 1998-05-29 2000-05-31 Block Drug Company Inc. Antimicrobial denture adhesive and cleanser compositions
US6267590B1 (en) 1999-11-24 2001-07-31 Agion Technologies, Llc Antimicrobial dental products
US20110229534A1 (en) 2006-10-05 2011-09-22 The Trustees Of Columbia University In The City Of New York Non-Irritating Oral Care Formulations
RU2444349C2 (en) 2009-12-08 2012-03-10 Марина Николаевна Бобешко Modified adhesive composition for blade denture fixation
EP2536379A2 (en) 2010-02-19 2012-12-26 The University Of South Dakota Rechargeable long-term antifungal denture materials
US20130014671A1 (en) 2011-07-11 2013-01-17 Yu-Hong Tzeng Antimicrobial dental material
US20140288171A1 (en) * 2008-12-16 2014-09-25 The Board Of Regents Of The University Of Texas System Acrylic polymers containing metallic nanoparticles
WO2015006087A1 (en) * 2013-07-08 2015-01-15 3M Innovative Properties Company Hardenable dental composition containing a mixture of agglomerated and aggregated nano-particles, kit of parts and use thereof
CL2014003518A1 (en) * 2014-12-24 2015-03-20 Univ Concepcion A composition of a masterbatch useful in the elaboration of dental prostheses and its elaboration process.
US9034354B2 (en) 2012-05-23 2015-05-19 Musc Foundation For Research Development Bacteriostatic and anti-collagenolytic dental materials through the incorporation of polyacrylic acid modified CuI nanoparticles

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6679937B1 (en) * 1997-02-24 2004-01-20 Cabot Corporation Copper powders methods for producing powders and devices fabricated from same
US6423762B1 (en) * 1998-09-30 2002-07-23 Block Drug Company, Inc. Denture adhesive compositions comprising a polymeric activator
US20120294919A1 (en) * 2011-05-16 2012-11-22 Basf Se Antimicrobial Silver Silica Composite
CL2015003781A1 (en) * 2015-12-30 2016-06-03 Univ Chile Process of preparation of dental and orthopedic acrylic materials with antibacterial properties using copper nanoparticle technology

Patent Citations (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3476854A (en) 1966-08-08 1969-11-04 Coe Lab Inc Antifungal resinous dental compositions and articles
US4332791A (en) 1980-04-29 1982-06-01 Blendax-Werke R. Schneider Gmbh & Co. Toothpaste active against plaque comprising a copper compound and a silica polishing agent
EP0081962A2 (en) 1981-12-08 1983-06-22 Warner-Lambert Company Denture cleansing composition
EP0400080B1 (en) 1988-02-11 1992-09-16 Btg International Limited Denture protection
EP0471396A1 (en) 1990-08-16 1992-02-19 Unilever N.V. Dental compositions containing stabilized copper
EP1003791A1 (en) 1998-05-29 2000-05-31 Block Drug Company Inc. Antimicrobial denture adhesive and cleanser compositions
US6267590B1 (en) 1999-11-24 2001-07-31 Agion Technologies, Llc Antimicrobial dental products
US20110229534A1 (en) 2006-10-05 2011-09-22 The Trustees Of Columbia University In The City Of New York Non-Irritating Oral Care Formulations
US20140288171A1 (en) * 2008-12-16 2014-09-25 The Board Of Regents Of The University Of Texas System Acrylic polymers containing metallic nanoparticles
RU2444349C2 (en) 2009-12-08 2012-03-10 Марина Николаевна Бобешко Modified adhesive composition for blade denture fixation
EP2536379A2 (en) 2010-02-19 2012-12-26 The University Of South Dakota Rechargeable long-term antifungal denture materials
US20130014671A1 (en) 2011-07-11 2013-01-17 Yu-Hong Tzeng Antimicrobial dental material
US9034354B2 (en) 2012-05-23 2015-05-19 Musc Foundation For Research Development Bacteriostatic and anti-collagenolytic dental materials through the incorporation of polyacrylic acid modified CuI nanoparticles
WO2015006087A1 (en) * 2013-07-08 2015-01-15 3M Innovative Properties Company Hardenable dental composition containing a mixture of agglomerated and aggregated nano-particles, kit of parts and use thereof
CL2014003518A1 (en) * 2014-12-24 2015-03-20 Univ Concepcion A composition of a masterbatch useful in the elaboration of dental prostheses and its elaboration process.

Non-Patent Citations (38)

* Cited by examiner, † Cited by third party
Title
CALDERONE RAFONZI WA: "irulence factors of Candida albicans", TRENDS IN MICROBIOLOGY., vol. 9, no. 7, 2001, pages 327 - 35
CANABARRO A.VALLE C.FARIAS MR.SANTOS FBLAZERA M.WANKE B.: "Association of subgingival colonization of Candida albicans and other yeast with severity of chrionic periodontitis", J PERIODONT RES, vol. 48, 2013, pages 428 - 432
CHATTERJEE AKRUCHIRA CTARAKDAS B.: "Mechanism of antibacterial activity of copper nanoparticles", NANOTECHNOLOGY, vol. 25, no. 13, 2014, pages 135101, XP020260067, DOI: 10.1088/0957-4484/25/13/135101
CIOFFI, N.TORSI, L.DITARANTANO, N.TANTALILLO, G.GHIBELLI, L.SABBATINI, L.BLEVE-ZACHEO, T.D'ALESSIO, M.ZAMBONIN, PG.TRAVERSA, E.: "Copper nanoparticle/polymer composites with antifungal and bacteriostatic properties", CHEM. MATER, vol. 17, 2005, pages 5255 - 5262, XP002498498, DOI: 10.1021/cm0505244
CORREA HERNÁNDEZ; SEBASTIÁN ADOLFO: "Preparacion de Resinas Acrilicas cargadas con nanoparticulas de cobre y sus propiedades antimicrobianas frente a Candida Albicans (Resumen)", 1 January 2012 (2012-01-01), pages 1 - 2, XP009512610, Retrieved from the Internet <URL:http://www.repositorio.uchile.cl/handle/2250/112937> [retrieved on 20170417] *
CORREA, S.: "Preparation de Resinas Acrilicas cargadas con nanopartfculas de cobre y sus propiedades antimicrobianas frente a Candida Albicans", INSTITUTO DE CIENCIAS ODONTOLOGICAS, 2012
DOUGLAS LJ.: "Candida biofilms and their role in infection", TRENDS IN MICROBIOLOGY., vol. 11, no. 1, 2003, pages 30 - 6
GENDREAU, L.Z.G. LOEWY: "Epidemiology and Etiology of Denture Stomatitis", JOURNAL OF PROSTHODONTICS, vol. 20, no. 4, 2011, pages 251 - 260
GONZALEZ, J.P.: "Instituto de Ciencias Odontologicas", 2013, UNIVERSIDAD DE CHILE, article "Sfntesis de materiales bactericidas basados en nanopartfculas metalicas y biopolfmeros para terapia periodontal odontologica"
GRASS, G.C. RENSINGM. SOLIOZ: "Metallic Copper as an Antimicrobial Surface", APPLIED AND ENVIRONMENTAL MICROBIOLOGY, vol. 77, no. 5, 2011, pages 1541 - 1547, XP055078911, DOI: 10.1128/AEM.02766-10
HUMBERTO PALAZA , RAUL QUIJADA , KATHERINE DELGADO : "Antimicrobial polymer composites with copper micro- and nanoparticles: Effect of particle size and polymer matrix", JOURNAL OF BIOACTIVE AND COMPATIBLE POLYMERS, 1 July 2015 (2015-07-01), pages 1 - 15, XP055396747, ISSN: 0883-9115, DOI: 10.1177/0883911515578870 *
HUMBERTO PALZA: "Antimicrobial Polymers with Metal Nanoparticles", INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES, vol. 16, no. 1, 19 January 2015 (2015-01-19), pages 2099 - 2116, XP055353580, ISSN: 1422-0067, DOI: 10.3390/ijms16012099 *
KAMIKAWA, Y. ET AL.: "In Vitro Antifungal Activity against Oral Candida Species Using a Denture Base Coated with Silver Nanoparticles", JOURNAL OF NANOMATERIALS, vol. 2014, 2014, pages 6
LIU, YY.LIU, DM.CHEN, SY.TUNG TH.LIU TY.: "In situ synthesis of hybrid nanocomposite with highly order arranged amoorphous metallic copper nanoparticle in poli (2-hidroxyethyl methacrylate) and its potential for blood-contact uses", ACTA BIOMATERALIA, vol. 4, 2008, pages 2052 - 2058
MACHADO A.KOMIYAMA E.SANTOS S.JORGE A.BRIGHENTI F.KOGA-ITO C.: "In vitro adherence of Candida albicans isolated from patients with chronic periodontitis", J APPL ORAL SCI., 2010, pages 384 - 387
MONTEIRO, D.R. ET AL.: "Silver colloidal nanoparticle stability: influence on Candida biofilms formed on denture acrylic", MEDICAL MYCOLOGY, vol. 52, no. 6, 2014, pages 627 - 635
MUSIAL, W.KOKOL, V.VONCINA, B.: "Deposition and release of chlorhexidine from nonionic and anionic polymer matrices", CHEMICAL PAPERS, vol. 64, no. 3, 2010, pages 346 - 353
N. GONZALEZ, I. DE JESUS ET AL.: "Prevalence of subprosthesis stomatitis", vol. 13, 1 February 2009, AMC
NADZEYA V BEZNIS; BERT M WECKHUYSEN; JOHANNES H BITTER: "Cu-ZSM-5 Zeolites for the Formation of Methanol from Methane and Oxygen: Probing the Active Sites and Spectator Species", CATALYSIS LETTERS, vol. 138, no. 1-2, 4 June 2010 (2010-06-04), pages 14 - 22, XP019815225, ISSN: 1572-879X, DOI: 10.1007/s10562-010-0380-6 *
NAM K-YLEE C-HLEE C-J: "Antifungal and physical characteristics of modified denture base acrylic incorporated with silver nanoparticles", GERODONTOLOGY, vol. 29, no. 2, 2012, pages e413 - e9
PALZA, H.: "Antimicrobial Polymers with Metal Nanoparticles", INT. J. MOL. SCI., vol. 16, 2015, pages 2099 - 2116, XP055353580, DOI: 10.3390/ijms16012099
PALZA, H.QUIJADA, R.DELGADO, K.: "Antimicrobial polymer composites with copper micro- and nanoparticles: Effect of particle size and polymer matrix", JOURNAL OF BIOACTIVE AND COMPATIBLE POLYMERS, 15 January 2015 (2015-01-15)
PALZAY TON- THAT, TM.JUNGNICKEL, BJ. ET AL.: "Water diffusion into transcrystalline layers on polypropylene", J. APPL. POLUM. SCI., vol. 74, 1999, pages 3275 - 3285
PARK, S.E. ET AL.: "Candida albicans Adherence to Surface-Modified Denture Resin Surfaces", JOURNAL OF PROSTHODONTICS, vol. 17, no. 5, 2008, pages 365 - 369
PUSATERI CRMONACO EAEDGERTON M.: "Sensitivity of Candida albicans biofilm cells grown on denture acrylic to antifungal proteins and chlorhexidine", ARCHIVES OF ORAL BIOLOGY, vol. 54, no. 6, 2009, pages 588 - 94, XP026128396, DOI: 10.1016/j.archoralbio.2009.01.016
RAVISHANKAR RAI V.JAMUNA BAI A.: "Nanoparticles and their potential application as antimicrobials", SCIENCE AGAINST MICROBIAL PATHOGENS: COMMUNICATING CURRENT RESEARCH AND TECHNOLOGICAL ADVANCES, vol. 1, no. 1, 2011, pages 10
REDDING SBHATT BRAWLS HRSIEGEL GSCOTT KLOPEZ-RIBOT J.: "Inhibition of Candida albicans biofilm formation on denture material", ORAL SURGERY, ORAL MEDICINE, ORAL PATHOLOGY, ORAL RADIOLOGY, AND ENDODONTOLOGY, vol. 107, no. 5, 2009, pages 669 - 72, XP026098997, DOI: 10.1016/j.tripleo.2009.01.021
REN, G. ET AL.: "Characterisation of copper oxide nanoparticles for antimicrobial applications", INTERNATIONAL JOURNAL OF ANTIMICROBIAL AGENTS, vol. 33, no. 6, 2009, pages 587 - 590, XP026043140, DOI: 10.1016/j.ijantimicag.2008.12.004
SARDI J.DUKE C.MARIANO F.PEIXOTO I.HOFLING J.GONCALVES B.: "Candida spp. in periodontal disease: a brief review", J ORAL SCIENCE., vol. 52, no. 2, 2010, pages 177 - 185
SCHALLER MBORELLI CKORTING HCHUBE B.: "Hydrolytic enzymes as virulence factors of Candida albicans", MYCOSES, vol. 48, no. 6, 2005, pages 365 - 77
SILVA, S. ET AL.: "he effect of silver nanoparticles and nystatin on mixed biofilms of Candida glabrata and Candida albicans on acrylic", MEDICAL MYCOLOGY, vol. 51, no. 2, 2013, pages 178 - 184
THEIVASANTHI, T.: "Studies of Copper Nanoparticles Effects on Micro-organisms", ANNALS OF BIOLOGICAL RESEARCH, vol. 2, no. 3, 2011, pages 368 - 373
URZUA B.HERMOSILLA G.GAMONAL J.MORALES-BOZO I.CANALS M.BARAHONA S. ET AL.: "Yeast diversity in the oral microbiota of subjects with periodontitis: Candida albicans and Candida dubliniensis colonize the periodontal pockets", MED MYCOL., vol. 46, 2008, pages 783 - 93
WEBB BCTHOMAS CJWILLCOX MDHARTY DWKNOX KW: "Candida-associated denture stomatitis, Aetiology and management: a review", FACTORS INFLUENCING DISTRIBUTION OF CANDIDA SPECIES IN THE ORAL CAVITY, AUST DENT J, vol. 39, no. 11, 2011, pages 711 - 9
WILLIAMS DWKURIYAMA TSILVA SMALIC SLEWIS MA: "Candida biofilms and oral candidosis: treatment and prevention", POSTGRAD MED J, vol. 78, 2002, pages 455 - 459
WILSON, SJ1WILSON, HJ: "The release of chlorhexidine from modified dental acrylic resin", J ORAL REHABIL., vol. 20, no. 3, May 1993 (1993-05-01), pages 311 - 9, XP002730771, DOI: 10.1111/j.1365-2842.1993.tb01613.x
YEN-YU LIU , DEAN-MO LIU , SAN-YUAN CHEN , TSAN-HAU TUNG , TSE-YING LIU: "In situ synthesis of hybrid nanocomposite with highly order arranged amoorphous metallic copper nanoparticle in poli (2-hidroxyethyl methacrylate) and its potential for blood-contact uses", ACTA BIOMATERALIA, vol. 4, no. 6, 1 November 2008 (2008-11-01), pages 2052 - 2058, XP025535868, ISSN: 1742-7061, DOI: 10.1016/j.actbio.2008.05.022 *
ZISSIS AYANNIKAKIS SHARRISON A.: "Comparison of denture stomatitis prevalence in 2 population groups", INT J PROSTHODONT, vol. 19, no. 6, November 2006 (2006-11-01), pages 621 - 5

Also Published As

Publication number Publication date
WO2023021440A1 (en) 2023-02-23
CO2024003209A2 (en) 2024-05-30
US20210400984A1 (en) 2021-12-30
EP3461335A1 (en) 2019-04-03
US20190021333A1 (en) 2019-01-24
EP3461335A4 (en) 2019-09-18
CL2015003781A1 (en) 2016-06-03
AR126809A1 (en) 2023-11-15
MX2018008122A (en) 2019-05-30
US11134687B2 (en) 2021-10-05

Similar Documents

Publication Publication Date Title
Bapat et al. The use of nanoparticles as biomaterials in dentistry
Makvandi et al. Polymeric and inorganic nanoscopical antimicrobial fillers in dentistry
Busscher et al. Biofilm formation on dental restorative and implant materials
Noronha et al. Silver nanoparticles in dentistry
Yin et al. Use of silver nanomaterials for caries prevention: a concise review
Allaker et al. Nanoparticles and the control of oral infections
Gleiznys et al. Candida albicans importance to denture wearers. A literature review
Farhadian et al. Streptococcus mutans counts in patients wearing removable retainers with silver nanoparticles vs those wearing conventional retainers: A randomized clinical trial
Loncar et al. Ozone application in dentistry
Lubojanski et al. Application of selected nanomaterials and ozone in modern clinical dentistry
Schmalz et al. Biofilms on restorative materials
Butrón Téllez Girón et al. Therapeutic use of silver nanoparticles in the prevention and arrest of dental caries
Allaker et al. Nanoparticles and the control of oral biofilms
JP2019518785A (en) Compositions and methods for inhibiting and preventing biofilm formation
Pirmoradian et al. Remineralization and antibacterial capabilities of resin-based dental nanocomposites
Glowacka-Sobotta et al. Nanotechnology for dentistry: prospects and applications
Grumezescu Nanobiomaterials in dentistry: Applications of nanobiomaterials
Kannan et al. Recent updates and feasibility of nanodrugs in the prevention and eradication of dental biofilm and its associated pathogens–a review
Alavi et al. Bioresponsive nanotechnology in pediatric dental drug delivery
RU2414882C1 (en) Antibacterial material for bases of removable teeth prostheses
WO2017113030A1 (en) Method for producing orthopaedic and dental acrylic materials having antimicrobial properties, using copper nanoparticle technology
Krishnamurthy et al. Role of nanomaterials in clinical dentistry
Fernandes et al. Improving antimicrobial activity of dental restorative materials
CN106309740A (en) Drug for cleaning oral cavities
Sati et al. Nanoparticles and inert coating materials: a potential enhancer of antimicrobial property of polymethyl-methacrylate (PMMA) based denture

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 16880234

Country of ref document: EP

Kind code of ref document: A1

WWE Wipo information: entry into national phase

Ref document number: MX/A/2018/008122

Country of ref document: MX

NENP Non-entry into the national phase

Ref country code: DE

WWE Wipo information: entry into national phase

Ref document number: 2016880234

Country of ref document: EP

ENP Entry into the national phase

Ref document number: 2016880234

Country of ref document: EP

Effective date: 20180730